A 



-fit. v 

v 0o 






- V^ 






$ ^ 



,0o y 










• V 







*V *„ 









c^ 









\ X °, & C '' 



'■■ ,, >* .'& 



/ •* 



V 



r> 



o 












$ *±, - *> %■ ' 



&■%. 



C */ ,\. O ,V V 






/ ,. V 



V - ^ ,\\ X 



\ 







"O 



b X 












,0 












<• 



cP % % 



c*v 



^^ v 



.#'% 










%. 


e* 




\ 




^' 


• r >. 


/ 








8 * 


•z* 


o 





x ,\\ 







- - V 



v 



o v «■ 









,vN 



■r-- 






""''./ 



^ v^ 









vV O */ ',, 'c- 



iV A 












y V, j 
















■X* 



: 









V 






*0 O. 






V 



O X 



r*. v u 






% ,^ V 






x v - 






LU 









MY FRIEND, 

JAMES E. MOONEY, 

PRESIDENT OF THE AMERICAN OAK LEATHER CO., CINCINNATI, OHIO, 

WHO HAS DEVOTED HIS LIFE TO THE MANUFACTURE OF LEATHER OF 

ALL KINDS, AND HAS DONE MORE THAN ANY OTHER MAN TO 

BRING TANNING EXTRACTS INTO GENERAL USE, 

I Dedicate this Book. 






/ 




PREFACE 

TO THE SECOND EDITION 



After nearly two years spent in the thorough revision, and 
the almost re-writing of this book, necessary on account of the 
many improvements in the manufacture of leather, the time 
has come to prepare the preface. 

The object which the author has kept constantly in view has 
been to supply his readers with practical and useful informa- 
tion upon such subjects as come within the scope of the book, 
and in as condensed a form as possible. He has given no space 
to mere theorizing, as he feels that he can be of greater use in 
setting forth good technical information, combined with suita- 
ble illustrations. The reader of a work of this character is 
necessarily looking for help in his particular field of industry, 
and is much better pleased to find the subject clearly expounded 
than to wade through pages of purely theoretical matter. 

The tanner's trade, like most other trades, has in the past 
been followed and carried out by rule of thumb rather than by 
scientific guidance. But this is steadily and rapidly changing ; 
chemistry having become the handmaid of all the industries, 
the chemist is necessarily a part of the personnel of every 
large tannery, and in all departments of leather manufacture 
he is making his influence felt for good. 

During the past fifteen years the leather industry of the 
United States has made greater strides than in all of the pre- 
vious centuries of its existence. The chrome process has been 
introduced, and tanning extracts havecome into general use, 

(v) 



VI PREFACE TO THE SECOND EDITION. 

and the world largely owes its progress, in these directions, to 
the United States. True, Germany led in the theoretical re- 
search regarding the use of chrome, but it remained for the 
United States to make this invention a practical success. 

We are ever traveling onward, and while it may by some be 
considered that the duty of 15 per cent, on hides and calf-skins 
might be an impediment, it can readily be overcome by our 
superior machinery and skill, and thus will we be able still to 
hold our foreign trade. 

While this industry has progressed from the simplest and 
most primitive to its present state, it is not yet perfect. The 
author would therefore admonish every manufacturer of leather 
to be on the lookout for all new improvements, and when found 
to be practicable to adopt them, as only in this way can he 
keep "up-to-date," and thus be saved from being relegated to 
the rear. It is much easier to go backward than to go forward. 

He desires especially to acknowledge his indebtedness to 
the Shoe and Leather Reporter for much valuable data gathered 
from its columns, and to all other trade papers from which he 
has taken any matter, not specially acknowledged in the body 
of the book. 

Charles Thomas Da,vis. 

Washington, D. C, 
605 Seventh Street, October i, 189J. 



M 



CONTENTS. 



CHAPTER I. 
Water and Pumps. 

PAGE 

Location of tanneries and currying shops in the United States ; Advan- 
tages of locations upon rivers and streams; Important position of 
water in tanning ; Most important admixtures of water and their in- 
fluence in tanning I 

Distinction of water as hard and soft ; Admixtures of spring and well 
water ...„......••• 2 

Points to be considered in determining the qualities of water for tanning 
purposes ; Reasons for swelling or plumping hides intended for sole 
leather ........-■■■• 3 

Temperature of the water used for preparing the hides ; Methods for de- 
termining the constituents of water . . 4 

Process of determining the hardness of water by a soap solution . . 5 

Determination of total hardness 6 

Determination of permanent hardness ; Softening water ... 9 

Use of borax for purifying water 10 

Pumps ; Prominence of pumping machinery among the various branches 
of engineering ............ 12 

Classes of pumps commonly used for raising water from wells ; Lifting 
or atmospheric pumps and their action ....... 13 

Limit of height to which water can be raised from wells by common at- 
mospheric pumps ........... 14 

Importance of a uniform temperature of the water in the manufacture 
of waxed calf; The Pohle system of pumping water by compressed 
air 15 

The Pohle Air Lift Plant at the works of the Henry Lang Co., Newark, 
N. J., described and illustrated 19 

CHAPTER II. 

Animal Skin. 

Classes of raw products with which the tanner has to deal ; Structure of 

the animal skin ; Composition of the epidermis 21 

( vii ) 



viii CONTENTS. 

PAGE 

On what the quality of the leather -which can be produced from a skin 

depends; A transverse section of the skin, described and illustrated . 22 
Conversion of the connective tissue fibres into glue . . . .23 
Behavior of skins under various conditions ; Chemical and morpholog- 
ical constitution of the skin 24 

Preparation of coriin 25 

Swelling influences of natural waters upon the coriin ; Effect of too 

long liming ............. 2G 

Preparation of connective-tissue substance ...... 27 

Swelling influence of acids upon the skin fibres 28 



CHAPTER III. 

Vegetable Tanning Materials. 

Rutea; Kino; Malabar or East Indian kino; Gambier ; Catechu or 
terra japonica . . . . . . . . . . . .29 

Gall-nuts 30 

Galls (Knoppern); Chinese gall-nuts; Rove; Sumach ; Sicilian sumach ; 
Italian sumach ........... 31 

Spanish sumach ; Tyrol sumach ; French sumach ; Tezera sumach ; 

American sumach ; Swedish sumach ; Valonia 32 

Divi-divi ; Myrobalans ; Bublah ; Logwood ; Fustic . . . .33 
Weld ; L,arch bark ; Fir bark ; Hemlock bark ; American hemlock ex- 
tract ; Oak bark 34 

Canaigre ............. 35 

Prof. Forbes on the value of canaigre tanning materials ; Quebracho . 36 
Discovery of the valuable tanning properties of quebracho ; Home of 
the quebracho tree ......:.... 37 

Prof. Eitner on the uses of quebracho ....... 38 

Sample of leather tanued with quebracho extract; Analysis of que- 
bracho ............. 39 

Statistics of exports of quebracho from the Argentine Republic ; Statis- 
tics of the American export trade in sole leather to Germany ; Forests 
of quebracho trees in the Argentine Republic ..... 40 

Advantages of the use of quebracho ; Process for using pure quebracho 

wood for sole leather in Buenos Ayres ; First or coloring liquor . . 41 
Second liquor ; Third liquor ; Method for employing quebracho with 
oak bark for sole leather in Europe ....... 42 

Loss in export trade in sole leather of the United States . . . .43 

Cost of quebracho bark ; Palmetto root ....... 44 

Chestnut oak wood ; Walnut bark ; Iyombardy poplar bark ; Elm bark; 
Horse-chestnut bark ; Phyllocitannic acid ; iFsculotannic acid . . 45 



CONTENTS. ix 

PAGE 

Horse-chestnut extract ; Willow bark ; Alder bark ; Beech bark ; Pro- 
tacese barks ; Snouba bark (scorza rosa) ...... 46 

Ratanky root ; Avens root ; Tormentil root ; Sassafras root ; Geranium 
Wallachianum ; Mesquite oak and live oak barks ; Mimosa . . 47 



CHAPTER IV. 

Leaching ; The Barkometer ; Bark Mills ; Bark Conveyer ; The 

Tan Press. 

Cardinal points to be considered in leaching l . ..... 48 

The gravity system generally employed by American tanners and ex- 
tract makers ; Illustration of the most common way of leaching ; Ab- 
solute necessity of slow leaching ........ 49 

General rule for the head leach ; The ideal leach 50 

The most seriously defective system of leaching . . . . .51 

Leach pumps of the Vaughn Machine Co., Peabody, Mass.; Regula- 
tion of the temperature of the liquors in leaching . . . .52 

The problem of properly leaching bark ....... 53 

How the difficulty of packing may be overcome ; Manner of pumping . 54 
Taking advantage of the factor "percolation ;" Limit to the length of 

the column in any one leach ; Advantage of ten or more leaches . 55 
Temperature of the water or liquor on the tail leaches ; Check on the 
efficiency of the leaching ......... 56 

Loss in tanning substance of the bark in the layaways; Use of the spent 
liquor from "rockers" on the tail leach ; Object of applying a mel- 
low liquor, weak in tanning substance, to a green hide from the beam 
house .............. 57 

System of leaching bark in use by the American Oak Leather Co., Cin- 
cinnati, Ohio ; Stephen Dow & Co., and F. C. Cottle & Son, and 
Beggs & Cobb's systems of leaching hemlock bark . . . .58 

Preference for pumping leaches more frequently ; Flooding leaches ; 
Great attention paid to the grinding of bark ...... 59 

Ledger account for each leach ; The Press-leach system . . . .60 

The barkometer and its application ........ 62 

Bark mills ; The earliest patent for a bark mill awarded to C. Foss . 63 
A. Bull's patent ; Main object in grinding bark ; Fads in the bark busi- 
ness 64 

Reform brought about by Dr. H. F. Starcke's analyses of " spent tan " . 65 
Various constructions of bark mills ; Bark cutter (Jones' patent) made 
by the Vaughn Machine Co., Peabody, Mass. . . . . .66 

Automatic knife grinder for the Jones patent bark cutter and other cut- 
ters ; Bark conveyer patented by Oliver A. Zane, of Peabody, Mass . 68 
The tan press made by William F. Martin, Salem, Mass. . . .71 



X CONTENTS. 

CHAPTER V. 
Tanning Extracts. 

PAGE 

Growth in the use of extracts ; Tanning extracts in common use in the 
United States ; Manufacture of tanning extract from the chestnut tree 
and chestnut oak tree 74 

Concentration of the liquor in the vacuum pan 75 

Preparation of hemlock extract ; Boiling point of water ; Similarity of 
the manufacture of tanning extracts to the process of extracting sugar. 76 

Decolorization of the liquor before concentration ; Examination of tan- 
ning extracts 77 



CHAPTER VI. 

Soaking and Softening. 

Process of soaking bides as recommended by a German tanner ; Soak- 
ing hides in wheels and in a water-pit or box . . . . .78 

Preparation of hides and skins for soaking ...... 79 

Treatment of foreign salted hides and skins, dry salted hides, kips, etc., 
and dried hides and skins 80 

Reasons for the neglect by tanners of foreign hides and skins ; Neces- 
sity of the preparatory work being thorough . . . . .81 

Usual mode of softening dry hides for sole leather ; Chemical soak ; Di- 
rections for working various kinds of hides ...... 82 

Use of borax for softening water ; Use of pure water in the soaks . . 83 

Time required for soaking calf-kid and light hides ; Softening ; Hide 
mills and their construction ; Softening mill in use by the morocco 
and kid tanners of Philadelphia, Penna. ...... 84 



CHAPTER VII. 
Deputation or Unhairing. 

Definition of a depilatory ; Depilous skins ; Different methods for ac- 
complishing depilation ; Preparation and properties of lime 

Objections to the use of lime . . . . . . . . . . 

Restoration of the suppleness to upper, morocco and other kinds of 
leather ; Bating ; Recapitulation of the inconveniences of the liming 
process ; Raising ........... 

Primitive manner of removing the hair ; Necessity of properly prepar- 



CONTENTS. XI 

PAGE 

ing the hides or skins for the beam house ; Proper condition of hides 
for limed stock ; Neglect of the work at the lime pits . . . .89 

Proper treatment of calf-skins in the limes ; Replacement of lime in de- 
pilating by acid liquors .......... 90 

Construction and arrangement of lime vats ; Preparation of a new vat ; 
Dead, weak and live vats ......... 91 

Operation of raising ; Time employed for liming ; The power reel ; 
American practice of putting hides through the soaks and limes ; Im- 
possibility of giving exact or arbitrary rules for liming and handling. 92 
Arsenic and its use in lining of goat skins ; Economies and improve- 
ments in lining and bating ......... 98 

Use of lime and dog-pure in the beam house ; Action of the lime ; Re- 
moval of grease in the lining of sheepskins . . . . .94 

The disease known as itch and objection to scabby skins . . .95 

The white itch and its cause 96 

Depilating with sodium sulphide ; Prof. Fiebing on this subject . . 97 
Method of using sodium sulphide in connection with lime . . .98 
Enumeration of the advantages obtained by the use of sodium sulphide 99 
On what the value of sodium sulphide as a depilatory depends ; John W. 
Stevenson on the sulphide of sodium process ..... 100 

Method of using sulphide of sodium as a depilating agent . . . 102 
Most striking effect of sulphide of sodium in the limes ; Explanation of 
the property of sulphide of sodium of bringing back the grain to its 
fresh, green state ........... 104 

Summary of the good qualities of sulphide of sodium ; Undesirable 
qualities of sulphide of sodium ........ 105 

Aging of alum-tawed glove-kid 106 

Reasons why a green skin is fiat and unelastic as compared to well- 
tanned leather ; A German opinion on the use of sulphide of sodium 107 
Main requisite demanded of a depilatory ; Arsenic as a depilatory . . 108 
Combination of sulphide of arsenic with lime ; Action of sulphide of so- 
dium and of sulphate of arsenic and lime ...... 109 

Action of lime alone ; Rapidity of the action of arsenic-lime . . . 110 
Comparison of results obtained by arsenic with those obtained by sul- 
phide of sodium Ill 

Constitution of the hide; Nature of the grain of the hide; Action of de- 
pilatories on the true skin and on the grain; Cause of the inner rotten- 
ness of leather 112 

Effect of allowing putrefaction to progress; Selection of skins in the 
beam-house; Depilating with charcoal ....... 113 

William Anderson's method of depilating with charcoal; Depilation 
with sulphide of barium; Foley's process ...... 114 

Advantages of this process over the liming process 115 

"Working-out and unhairing all kinds of hides and skins without limes, 
bate, drench or beaming — the Peirson-Moor process; Chemistry of de- 
pilatories 116 



xii CONTENTS. 

PAGE 

Results of the analysis of liquor from an old, well-plunged lime pit 117 

Proximate analysis of red arsenic ; Investigation of the part played by 

red arsenic in the mixture of it with lime . . . . . .118 

Investigation of the depilatory properties of calcium thioarsenite . . 119 
Depilation by sweating; Villon's experiment and conclusions drawn 

therefrom ............ 120 

The "cold-sweat" process and the "warm-sweat" method; Cause of 

"frieze;" "black spots " or "old grain;" Description of a building 

for sweating hides and skins ......... 121 

Care to be observed in sweating hides 124 

Effect of the sweating process; Advisability of the sweating process for 

imported hides 125 

Method of sweating 126 

Operation of the sweating process; The warm-sweating process . . 127 
Sweating fresh hides . . . . . . . . . . .128 

CHAPTER VIII. 
Unhairing and Freshing by Hand and Machinery. 

Interior view of the beam-house; The German form of beam and the 
unhairiug knife; Unhairing of hides and skins by the hand method 130 

Injury to hires in unhairing; The "short-hair knife;" Beam work in 
France 133 

Unhairing of slaughtered calf-skins fresh from the Paris market; Flesh- 
ing by the hand method; Fleshing knives described and illustrated 135 

German, or spring fleshers; Operation of fleshing; The saw-tooth flesher, 
described and illustrated ......... 136 

Turning steel described and illustrated; Going over the flesh-sides with 
the "worker" 137 

Counter-fleshing; A sure hand required to do the fleshing of a calf-skin; 
Soaking hides after fleshing by the hand process ..... 138 

Soaking hides in a steeping cistern after fleshing; How long should the 
hides soak after fleshing, and what indicates their readiness for 
scouring 139 

Fleshing and unhairing by machinery; The Vaughn improved fleshing, 
unhairing and working-out machine, illustrated and described . . 140 

The cylinders used with this machine, illustrated; Grinding lathe or 
cylinder and roll sharpening and turning- up machine made by the 
Vaughn Machine Co., described and illustrated 144 

Unhairing machines ; Whitney's "Jumbo " unhairing machine . . 146 

Whitney's patent combined unhairing, fleshing and working-out ma- 
chine 147 

Whitney's patent re-fleshing machine ....... 149 

Practical success of the unhairing and fleshing machines. . . .151 



CONTENTS. Xlll 

CHAPTER IX. 
Bating. 

PAGE 

Various terms applied to this process ; Reasons \vr13' the greatest risk in 

any beam-house is that of bating ........ 153 

Scientific investigation within recent times of the processes connected 

with the tanner's art; Objections to the use of manure bate; Action of 

manure bate ......... ... 154 

Bran bate; Necessity of removing the lime or other alkaline depilatories 

from hides and skins previously to tanning; Substitutes proposed and 

patents covering processes for bating 155 

C. T. Bate (coal-tar bate) invented by Peter S. Burns and Chas. S. Hull 

and manufactured by the Martin Dennis Chrome Tannage Co.; Other 

acids proposed for bating purposes ....... 156 

" Borol;" P. Hauff's patent ; Manner of bating ; Suggestions regarding 

the old form of manure bates; Bating high-limed goat skins . . 157 
Fermentive action of the bate; Best time for fine-hairing; Best bate for 

calf kid and sides; Borax and boracic acid as bates; Purpose of puring 

light leathers 158 

Method of puring; Consequence of leaving any lime in the stock . . 159 
Treatment of hides intended for sole leather; Bating dressing leather in 

the United States; Bate for sole leather 160 

Universality of the practice of reducing the hide or skin and objections 

to that practice ........... 161 

Puring sole leathers; Inability of getting colors right in glove leathers 

due to poor bating 162 

Properties of dog excrements; Preparation of dog-pure; Theory of dung 

bating 163 

Various substances employed as bates; Objections to the present method 

of bating; Usual method of bating. . . . . . . . 164 

England wheels for agitating the bate liquor; Scouring; Graining; Final 

soaking before placing the hides in the ooze ...... 166 



CHAPTER X. 

Handling and Plumping. 

Handling; Various methods of handling hides; Handling and transfer- 
ring the sides by the medium of a revolving device, such as a reel . 167 

Modes of connecting the sides; The hand reel; The rocker handler; Ap- 
paratus invented by U- C. England, described and illustrated . . 168 

Paddle wheels for handling and vats in which they revolve t . . .170 

Some European methods of handling; Handling the sides in the manu- 



xiv CONTENTS. 



PAGE 



facture of grain and split leather; Handling by means of a large revolv- 
ing drum; Gorsline's apparatus for handling 172 

Plumping; Plumping by means of sour liquor 173 

Distillation of the sour liquors as proposed by H. J. Botchford . . 174 
Plumping by means of sulphuric acid ; Introduction of this process by 

David Mac Bride 1 75 

Properties of sulphuric acid ......... 176 

Plumping by means of acetic acid 177 

Mineral acids for plumping; Lactic acid for plumping .... 178 



CHAPTER XI. 

LAYING-AWAY. 

Action of tannin; Probability of leather not being a chemical combina- 
tion of the animal substance with the tanning substance; Mr. Knapp's 
experiments in making leather without tanning elements . . . 179 

Final step in the process of tanning heavy hides and sides; Laying away 
the stock , 181 

Layers and periods for tanning the heaviest sole leather in this country; 
Laying away the packs in the manufacture of finer grades . . .182 

Various methods of passing the liquor; Jack for raising whole hides up 
in the lay-away vats . . . . . . . . . .183 

Float for whole hides ; Handling the sides in tanning heavy upper 
leather 184 



CHAPTER XII. 

Stoning. 
Stoning-jack made by J. T. Freeman & Co., Woburn, Mass . . . 185 

CHAPTER XIII. 

Splitting Leather. 

Perspective view of the cellar of ah upper leather tannery; Splitting 
machines; Splitting machine patented by Alpha Richardson; Early 
invention of Seth Boyden 186 

Richardson's Union Splitting Machine; The Belt Knife Splitting Ma- 
chine invented by Joseph F. Flanders and Jere A. Marden; Perspec- 
tive view of, the Union Splitting Machine; Attachment patented by 
John A. Enos; Leather-splitting as generally practiced . . . 188 



CONTENTS. XV 

PAGE 

Details of Enos's invention ......... 190 

Leather-splitting machine embodying Enos's invention .... 191 

Remedy of difficulties in splitting .....'.. 192 

Hints for splitting with the Union Splitting Machine .... 193 

The Belt Knife Leather Splitting Machine 194 

Instructions in regard to splitting leather 198 

Bassett's belt knife splitting machine; Improvement on grinder rigging 

for belt knife splitting machines .....*.. 201 
Removing the rubber roll from the Bassettt belt knife splitting ma- 
chine 202 

Robertson's grinding adjustment for belt knife splitting machines. . 203 



CHAPTER XIV. 

Scouring. 

Treatment of the leather after it has been split; Tools used in the hand 
method of scouring leather ... ...... 208 

Monk's scouring machine and the leathers on which it can be nsed . 209 
Scouring and setting out machine built by the Vaughn Machine Co., 
Peabody, Mass 212 



CHAPTER XV. 

Stuffing Leather ; Oils and Fats ; Testing Oils ; Water Proof- 
ing Leather. 

Hand stuffing ; Tempering upper leather ; When the hand process of 
stuffing leather is accomplished ; Objections to the hand method of 
stuffing ............. 215 

Drum stuffing; The best material to use in stuffing; Heating the drum . 216 
Filling the drum; Removing the goods; Setting the goods; Stoning . 217 

Reed and Winchester's stuffing drum 218 

Improvement in tramping drums invented by Dr. Friederich Knapp . 220 
Freeman's stuffing drum; Curriers' oils and greases; Definition of oils . 221 
Three different classes of bodies embraced in the name oil; Fixed or 
fatty oils; Volatile and essential oils; Mineral oils; Properties of fats . 222 

Most common and abundant fats; Cod oil 223 

Adulterants of cod oil; Chief seats of the cod fishery; Classification for 
cod liver oil; Chemical and physical characteristics of dark brown or 

tanner's cod oil 224 

Detection of adulteration of cod oil with mineral oils, brown seal and 
menhaden oils; Use of Bank and Straits oils as substitutes for cod oil. 225 



XVI CONTENTS. 

PAGE 

Degras; English sod oil 226 

French moellon oil; Tallow; Oleo-stearine ; Paraffine wax ; Principal 
stuffing used for upper leather ........ 227 

The "Ideal" grease; Neatsfoot oil ; Menhaden, Straits or Bank oil; Men- 
haden fisheries; Preparation of the oil ....... . 228 

Porpoise oil; Tunny oil; Neatsfoot oil . 229 

Degras; Manufacture of degras in France; Mixture of degras and fish 
oil 230 

Vickers' degras; Early use of sod oil or French degras; Former manu- 
facture of sod oil; Injurious effect of the sulphuric acid used in mak- 
ing sod oil; Method of getting rid of an excess of acid in sod oil. . 231 

Method used in France for tanning oil-dressed leather and for making 
sod oil; American process of oil dressing ...... 232 

European method of oil dressing 233 

The most valuable and characteristic property of genuine sod oil; The 
tanning principle of pure sod oil ; Amount of tanning principle in 
menhaden, Bank and Straits' oils, and in genuine cod oil . . 234 

On what the value of fish or cod oil as a leather lubricant depends; 
Paraffine wax . . . . : 235 

Glycerine; Changes created by the introduction of mineral salts in the 
manufacture of leather 236 

Production of glycerine; Properties of glycerine; Use of glycerine for 

oiling in the place of fat or degras 237 

Necessity of mixing glycerine with supplementary ingredients; Methods 
for effecting a better adherence of the glycerine to the leather . . 238 

Combination of glycerine with tannin; Practical method of stuffing with 
glycerine 239 

Testing oils; Simple tests for determining the amount of compounding 240 

Evil effects of the bad conditions of fats; Mode of distinguishing a gen- 
uine degras from simple fat emulsions ; Most usual adulteration of 
degras 241 

Borax; steam jacket kettles; Stuffing or fat liquoring with Palermo fig 

soap 242 

Formula for making fat liquors with Palermo fig soap; Fat liquors . 243 

Chromol fat liquors for chrome tanned leather, directions for use; 
Water-proof stuffing 244 

Water-proofing leather; The mineral process; Stuffing compounds; Par- 
affine wax for giving leather the quality of water-resisting . . . 245 
Formulae for producing water-proof leather 246 

CHAPTER XVI. 

Setting-out. 

Considerable amount of labor required in setting heavy leathers; Ston- 
ing-out, scouring and setting-out machine built by the Vaughn Ma- 
chine Co. _ 248 



CONTENTS. XV11 

CHAPTER XVII. 

Whitening and Shaving Leather. 

PAGE 

Various ways of whitening; French pattern of whitening slicker; Form 

of beam generally employed in currying shops ..... 250 
Union whitening and buffing machine made by J. T. Freeman & Co. 251 
Shaving machine; The Rood improved shaving machine, manufactured 
by the Vaughn Machine Co 254 

CHAPTER XVIII. 

Bracking Leather. 

Forms of blacking brushes in common use 256 

Leather blacking, coloring and dressing machine patented by Batch- 
elder, and built by the Vaughn Machine Co. ..... 257 

CHAPTER XIX. 

Machines for Rolling, Pebbung, Glassing or Polishing, 
Finishing, etc. 

The glazing machine one of the first steam-driven tools introduced into 
the trade; The Bowers rocker-motion leather finishing machine. . 263 

Improved iron glassing jack made by J. T. Freeman & Co.; Improved 
straight bed rolling or pebbling jack made by J. T. Freeman & Co. 266 

Martin's improved machine 267 

The Knox improved inclined bed leather finishing and pebbling ma- 
chine 268 

The Coombs pendulum jack, made by the Vaughn Machine Co. . . 271 

CHAPTER XX. 

Staking Machines. 

"Hand method" staking machine built by F. F. Slocomb & Co. . 273 

Staking machine built by the Vaughn Machine Co 274 

Staking machine built by Wm. F. Martin, Salem, Mass. . . . 275 



XV111 CONTENTS. 

CHAPTER XXI. 

Machine for Measuring Leather. 

PAGE 

Modes of selling leather; Sawyer's leather measuring machine . , 277 

The Union leather measuring machine 279 

The Bolton machine 281 



CHAPTER XXII. 

Mineral Tanning Substances — "Chrome," or Mineral Tannage — 

Characteristics oe Chrome-Tanned Leather — 

Currying — Dyeing. 

Principal mineral substances; Aluminium sulphate; Preparation of neu- 
tral aluminium sulphate; Properties of aluminium sulphate . . 282 

To make aluminium sulphate containing free sulphuric acid available 
for tanning purposes; Alum, its formation and properties . . . 283 

Splitting up of the alum in absorption by the skin tissue; Aluminium 
acetate and its properties; Advantages claimed for aluminium acetate. 284 

Chromium salts; Potassium bichromate, its manufacture and properties. 285 

Sodium bichromate; Calcium bichromate, strontium and barium and 
the neutral chromates of calcium, strontium and barium; Chromium 
alum; Chromic sulphate ......... 286 

Hyposulphite of soda; Ferric salts; Recommendation in the last century 
of tanning with ferric salts by D'Arcet; Bordier's patent; Attempted 
reintroduction by Knapp of tanning with ferric salts .... 287 

Preparation of an iron soap; Common salt and its importance in tan- 
ning; Varieties and preparation of common salt 288 

" Chrome " or mineral tannage; The first use of bichromates for tan- 
ning made by Cavalin, and his method; Impossibility of a practical 
application of this process ......... 289 

Knapp's patent for tanning with ferric salts and other metallic oxides; 
Patent for the preparation of a basic ferric sulphate and its use for 
tanning obtained by Pfanhauser; Knapp's new method of tanning 
with ferric salts . . . . . . . . . 290 

New and peculiar features claimed for this purpose by Knapp . . 291 

Nature of the leather prepared by Knapp's process; Additional patent 
applied for by Knapp for a somewhat different method of preparing 
ferric salt. 292 

Heinzerling's patented process for quick tanning with chromates and 
its execution ............ 293 



CONTENTS. XIX 

PAGE 

Directions for working the upper aud sole leather obtained by this pro- 
cess into shoes 295 

Advantages of chrome leather; Abandonment of the above mentioned 
methods of tanning on account of the defective quality of the product 
produced by them; Requisite characteristics of the mineral tanning 
substance. 296 

Usefulness of the salts of aluminium, iron and chromium ; The two 
methods of chrome tanning now in practical use; The two-bath pro- 
cess and the one-bath process; The Schultz patents and the Dennis 
patent; Treatment in the Schultz method 297 

Commercial leather of superior quality by the Schultz process first made 
by Robert H. Foederer, of Philadelphia, Pa., and Wm. Zahn, of 
Newark, N. J.; Simplification of the art of chrome tanning by the 
Dennis "one-bath " process 298 

Tanolin and its advantages 299 

Varieties of leather tanned by the Dennis process; Necessity of circum- 
spection when embarking in the new field of chrome tannage . . 300 

High standing of American morocco and kid manufacturers; Abandon- 
ment of the old currier style of shaving on the wooden beam face; 
Rapid increase in chrome tannage; Properties of chrome npper . . 301 

Competition of chrome tanning with bark; Impetus to the demand for 
sporting shoes ............ 302 

Tanning calf or goat skins by the chrome process ; Directions by the 
Martin Dennis Chrome Tannage Co. for using tanolin on calf or goat 
skins. . . 304 

Tanning sheep skins by the chrome process; Some patents for chrome 
tannage 306 

Information regarding the Dennis "one bath " process of chrome tan- 
nage; Application by the German tanners of chrome tanning to the 
production of a great variety of leathers ...... 307 

The Dennis tanning liquor; Specification of the patent .... 308 

The Dennis process of tanning leather; Specification of the patent . 313 

Characteristics of chrome leather ........ 319 

Currying chrome leather; Preparation and use of "fat liquors " . . 321 

To prepare chrome-tanned leather for dyeing; Patent granted to E. 
Avellis and Emil Koester of Berlin, Germany; Practical example of 
the process 322 

Dyeing chrome leather; Dyeing with neutral basic aniline colors; Dye- 
ing with acid aniline colors; Fixing alizarine colors; The best " all- 
round " mordant to be used on leather 323 

Dyeing leather with alizarine colors ; H. Koechlin and E. Knecht's 
method 324 



XX CONTENTS. 

CHAPTER XXIII. 

Kid or Morocco Leathers. 

PAGE 

Great revolution in morocco manufacturing in ten years by the intro- 
duction of the new agent, chrome; Patents issued to Augustus Schultz 

of New York City 326 

Reasons given by Mr. Schultz for taking out two patents; Assignment 

and transfer of Schultz's patents to various parties .... 327 
William M. Norris on the advantages of chrome tanning . . . 328 

Preparing the skins 330 

Lime vats in a kid morocco factory; Breaking, fleshing, unhairing, 

and slating machine 331 

Washing the skins 334 

Influence of the previous treatment of the raw pelt on the leather pro- 
duced by any one of the chrome processes; Liming and deliming; 

Slating 335 

The bran drench; Tawing according to the Schultz patent; Prepara- 
tion of the baths; Test for the completion of tanning .... 336 

Different constitution of the baths; Latitude in the amount of water to 
be used; Treatment of skins in a drum; The reel ..... 337 

Reasons for using more liquor and less concentrated baths when treat- 
ing skins in a reel rather than when treating them in a drum; Prepara- 
tion of the second bath .......... 338 

Change in the condition of the chromium of the first bath; No effect 
produced upon the skins by the bichromate of potash ; The essential 
discovery made by Schultz; No accurate determination of the chemi- 
cal reactions which take place in the skins ...... 339 

Treatment of the skins in the second bath; Opinions regarding the de- 
scriptions given in the two Schultz patents ...... 340 

Tanning goat-skins for kid leathers; Prof. Samuel P. Sadtler's experi- 
ments with goat skins 341 

Indication of plumping; Effect of introducing a skin into an acidulated 

bath . . 342 

The tan-vat used in the two-bath method of chrome tannage; Specifica- 
tion of Schultz's first patent (No. 291,784) 343 

Specification of Schultz's second patent (No. 291,785) . . . 345 

William M. Norris on Schultz's patents 346 

Further information by Mr. Schultz about his process; First bath; Sec- 
ond bath • 347 

Advantages of making leather by the Schultz process .... 348 

Specification of the Zahn patent ........ 349 

Explanation of chemical symbols ........ 351 

Reactions which take place in preparing the chrome bath; Rule for 
finding the combining weight of bichromate of potash . . . 352 



CONTENTS. XXI 

PAGE 

Function of the acid in the bath 353 

Rule for determing the proper amount of acid to use in connection with 

the hyposulphite of soda; Determination of the proper relation between 

the bichromate of potassium and the hyposulphite of soda . . . 354 
Sensitive condition of skins when saturated with chromic acid; Troubles 

due to the sulphurous acid ......... 355 

Putting-out machine; Object of putting-out; Vaughn's machine for 

putting-out 356 

Shute and Faulkner's seasoning machine 358 

Formula for seasoning 360 

Plans of the kid factory of F. Blumenthal & Co., Wilmington, Del. . 361 
India tanned goat; Sumac tanned skins; Drying loft in a morocco 

factory 364 

Finishing imitation of French kid 366 

Finishing room in a morocco factory ....... 367 

Finishing brushed kid; Finishing straight-grained goat .... 368 

View of drying loft in a morocco factory — showing the skins spread 

out 370 

Graining and the graining board ........ 371 

Rolling and glazing room in a morocco factory 372 

Finishing pebble-grain goat; Finishing oil-goat 373 

Coloring; Information about coloring by William M. Norris . . . 374 

Dongola calf 375 

The old processes of converting goat skins into Dongola and other fine 

leathers; Different processes through which goat-skins pass in their 

conversion into Dongola; Soaking ....... 376 

Milling; Liming; Unhairing; Bating 377 

Slating; Tanning; Striking-out; Dyeing or blacking; Drying . . . 378 



CHAPTER XXIV. 

Oak-Tanned Soee Leather — Unscoured and Scoured 
Leather — Cut Soi.es. 

Hides used; Placing the hides in the soaks; Changing the water in the 
soaks; Liming ............ 379 

Graining; Advantages of fleshing and unhairing by machinery; Warm 
bath for limed hides 380 

Necessity of carefully and thoroughly scudding the grain; Superiority 
of hides cured by Syracuse coarse salt; Use of borax for preserving 
hides; Sweated hides : 381 

Necessity of keeping a ledger account of each lot of hides put through 
the tannery; Suspension of the hides in rockers; Re-hanging the hides 
in the handlers; Liquors supplied to the rockers 382 



XX11 CONTENTS. 

PAGE 

Liquor in the handlers ; Lay-away vats ; Schedule of the time and 
strength of liquor employed in each layer 383 

Liquor used for the various layers; Handling the pack of hides; Laying 
away light hides ........... 384 

Splitting the hides and treatment of the sides; Drying and the best tem- 
perature for this process .......... 385 

Percentage of rough leather from various grades of hides; Treatment of 
hides for sumac leather; Rolling machine for sole leather . . . 386 

Cut soles 387 

Cut sole factory * . . .388 

Revolution in the trade in sole leather 389' 



CHAPTER XXV. 

Harness and Bei/ting Leather- 

Hides used for this variety of leather; Treatment of harness hides . . 390 
Effect of too concentrated solutions of tannins for skins and lighter 
hides; Belting for lighter purposes . ....... 391 

Chrome tannage for harness and belting leather; Quick tanning process; 
Currying harness leather ......... 392 

Currier's skirting; German harness leather ...... 395 

Preparation of -vache leather ......... 397 

Drum tannage ............ 399 

Indian harness leather; Sketch of the system by Walter G. McMillan . 400 
The system of tannage used in the Cawnpur factory; Analysis of water; 
Hides used ; Tanning material employed ; Experiments with Sal 

(Shorea Robusta) 401 

Sizes and weights of material employed; Mode of conducting the tan- 
ning process 402 

Currying 403 

Tests of new leathers; Points indicated by the experiments . . . 404 

Machine belt leather greased with tallow 405 

Currying the tallowed leather 406 

Currying strap butts for mill band and engine belts 407 

To remove grease from leather belting, etc 408 

Wet stretching machine for belt leather, built by the Vaughn Machine 
Co 409 



CHAPTER XXVI. 

Danish Leather. 

Definition of Danish leather; Nature of leather obtained by willow tan- 
nage; Use of glycerine for softening purposes 412 



CONTENTS. XXlll 

CHAPTER XXVII. 

Russet Leather. 

PAGE 

Material for russet leather; Uses of russet leather 414 

Preparation of russet leather; Proper way to split shoe leather . . 415 
Splitting card and strap leather; Light color on the leather; Printing the 

leather 416 

Dyeing the leather ........... 417 

CHAPTER XXVIII. 

Grain and Split Leather.— Satin Oil Finish ; Oil Grain ; Plow 
Grain ; Glove Grain ; Imitation Goat or Pebble Grain ; Imita- 
tion Kangaroo ; Imitation Seal ; Imitation Hog ; Wax Crimping 
Splits ; Flesh Splits ; Dongola, Buffed Leather, and Flexible 
Splits, with Stuffings, Pastes, Blacks, Finishes, etc. 

Qualities in upper leather looked for by buyers; English crown leather 

as an illustration of how nicely the grain is broken by agitation. . 418 
Bark used for the tannage for the varieties of leather under considera- 
tion; Hides used; Soaking the hides 419 

Splitting and fleshing; Liming; Unhairing; Bating 420 

Short-hairing and washing; Treatment in the handlers; Skiving, stoning 
and splitting; Running in a pin wheel ....... 421 

Milling; Scouring; Drying yard of an upper leather tannery; Stuffing; 

Various kinds of stuffing for different leathers 422 

Striking out the sides; Staining and blacking 424 

Finishing bright glove grain, imitation of goat and pebble grain and 

kangaroo chrome tannage; Crimping splits 425 

Gum tragacanth finish .......... 426 

Paste for upper splits and calfskins; Blacking for splits; Paste for wax 
stock ; Imitation seal and hog ........ 427 

Plow grain .............. 428 

Flesh splits; Stuffing for flesh splits 429 

Finishing coat for flesh splits; Finishing oil grain ; Bright finish for 
glove grain; Blue black color ......... 430 

Finishing satin oil leather; Imitation of goat or pebble grain finish; 
Kangaroo finish; Very bright pebble grain finish . . . . 431 

Blue black liquor for finishing; Buffed leather 432 

Flexible splits 433 

Degras 435 



XXIV CONTENTS. 



CHAPTER XXIX. 

Enameled Leather, Patent Leather, Furniture or Upholstering 
Leather, Regalia Leather. 

PAGE 

Hides used for the production of enameled and patent leather; Soaking, 
unhairing, fleshing and liming; Bating ....... 436 

Further treatment of the hides 437 

Tanning vats in patent leather factory; Materials employed for tanning. 438 

Splitting the hides; Re-tanning the hides and splits 439 

Scouring the hides and splits; Stuffing which has been found to be sat- 
isfactory ... 440 

Frame for stretching leather invented by Chas. P. Oliver and Theodore 

P. Howell 441 

Softening the hides and splits; Patching; Sorting; Grades of hand-buffed 

hides 443 

Grades of machine-buffed hides ; Kinds of leather the splits make ; 
Classes of buffing selected for japanning; Hide frames and their con- 
struction; Black enameled top leather such as in use for buggy and 
carriage tops; Preparation of daub of raw linseed oil . . . . 444 

Application of the daub ; Drying oven in patent leather factory ; The 
slicker coat; Preparation of enameled varnish ..... 446 

Final finishing coat; Smooth finished patent leather .... 447 

Preparation of the black vsrnish; Application of the varnish; Final coat 
of varnish ............ 448 

Preparation of finishing varnish ; Plain black buffings ; Furnishing or 
upholstering leather .......... 449 

Regalia leather; Notes; Management of the finishing room; Naphtha 
and turpentine as reducing agents ........ 450 

Brushes and other tools ; A good way to open enameled and patent 
leather which is stuck together; Preserving the gloss of patent leather; 

Renewing the surface of japanned leather 451 

Preparing the cut surface of split leather for manufacturing japanned or 
enameled leather ; Stephen J. Patterson's method for forming an 
artificial grain on the hide after it has been buffed or split . . . 452 

Japanned leather in imitation of alligator skin 453 

Linseed oil; Constituents of linseed 454 

Cold drawn oil; Ordinary linseed oil; Yield of oil by extraction; Prop- 
erties of linseed oil .......... . 455 

Constitution of linseed oil; Reactions of linseed oil with acids . . 456 
Detection of adulterations; Uses of linseed oil . . . . . . 457 

Commercial forms of linseed oil; Selection of the oil to be boiled; Chem- 
ical changes induced in linseed oil by exposure to the air ; Metallic 
oxides used in boiling linseed oil ....... . 458 



CONTENTS. XXV 



Reasons for boiling linseed oil ; Test for the drying qualities of boiled 
oil; The philosophy of the process of driving off by heat the mucilage 
from the seed 459 



CHAPTER XXX. 

Horse Leather. 

Origin of the manufacture of horse hides for foot wear; Foundation for 
a good finished product; Manipulation of the hides .... 461 

Tanning of the hides; Splitting; Cordovan 462 

Manipulation of the hides 463 

Wax finish on chrome-tanned horse hide butts (cordovan); Horse hides 
for enamel ............ 464 

Horse hides for plain enamel; Horse hides for memel .... .465 



CHAPTER XXXI. 

Aeeigator Leather. 

Alligator hunting industry in Louisiana; Scarcity of alligators . . 466 
Present chief source of alligator skins; Average price of alligator skins. 467 
Manipulation of the skins previous to tanning ; Tanning ; Treatment 
after tannine 468 



CHAPTER XXXII. 

Russia Caef. 

Process of making colored or Russia calf; Soaking ; Milling; Constitu- 
tion of the limes 470 

Fleshing and fine-hairing; Tanning; Division of tan-room; Strength of 
the liquors; Manipulation in tanning 471 

Strengthening and clearing the tanned stock; Fat liquoring . . . 472 

Coloring; Application of egg; Finishing manipulations; Another process 
for coloring 473 

Composition of colors 474 



xxvi CONTENTS. 



CHAPTER XXXIII. 

The Manufacture of Russia Leather — Russian Method of Pre- 
paring and Applying the Mordant and Dye — Manufac- 
ture of Birch Oie. 

PAGE 

Russia leather as made in Russia; Characteristics and uses of Russia 

leather 475 

Source of the peculiar odor of Russia leather; Locations of leather man- 
ufactories in Russia; Process of making Russia leather in Russia . 476 
Other processes of tanning. ......... 477 

Peculiar Russian process for freeing the hides from lime; Manufacture 

of Russia leather in Austria; Preparation of birch oil by the Russians. 478 
Preparation of birch tar or oil in America; Different claims made con- 
cerning the manufacture of Russia leather ...... 479 

Cause of the red color of Russia leather ; Method of manufacturing 
Russia leather in the United States ....... 480 

Dyeing the leather; Treatment of the leather after dyeing . . . 481 
Preparation of the mordant used in Russia ; Coloring matter used in 

Russia; Mode of dyeing 482 

Giving a brilliant appearance to red Russia leather; Graining. . . 483 
Black colored Russia leather; Manufacture of birch oil . . . . 484 

Fischerstroem's method of manufacturing birch oil ; Grouvelle and 
Duval-Duval's process .......... 485 

Payen's apparatus for repeating distillation in order to obtain an oil less 
colored; Products obtained by the distillation of one hundred parts; 
Birch oil and leather; Manner of obtaining birch oil . . . . 486 

Preparation of birch tar and birch tar oil . . . . . . . 487 

Russia odor to calf leather; Birch tar and pine tar — their differentiation. 488 



CHAPTER XXXIV. 

Weighing of Leather. 

No notable advances made in the art of weighting leather; Indication of 
the presence of sugar; Analysis of a sample of sole leather . . . 489 

CHAPTER XXXV. 

Tanning and Dyeing Furs and Hair-Skins. 

Tanning calf skins 491 

For tanning furs, peltries and deer skins 493 

In the process of cold tan; Dyeing fur skins 494 



CONTENTS. XXV11 

PAGE 

Latest developments in the dyeing of fur skins; Experiments with ursol 
colors ............. 495 

Methods for "killing the skin ;" Preparation of a degreasing liquid; 
Mordanting the skins 496 

Representative example of the method of dyeing; Dyeing rabbit skins 
golden brown; Dyeing goat skins and Thibet or wild goat skins . . 497 

Light brown for long-haired musk-ox; Dyeing imitation of seal-skin in 
clipped musk-ox; Imitation nutria in clipped rabbit; Intense black for 
angora goat or other similar skins ........ 498 

Directions for producing a blue-black tinge; Peculiar advantage in dye- 
ing with ursol colors; Appliances required for practical dyeing with 
ursol colors ............ 499 

Improvements relating to the manufacture of artificial fur, beaver and 
nutria; Weights and measures used in this chapter .... 500 



CHAPTER XXXVI. 
Tawing Lamb and Kid Skins for Glove Leather, Dyeing, etc. 

Preparation of the material for gloves; Soaking; Washing; Liming. . 501 
Unhairing; Fleshing; Drenching; Tawing; Softening and the mill used 

for this purpose , 502 

Ripening and selecting the skins for coloring; Coloring the skins; Black 

on glove skins ............ 503 



CHAPTER XXXVII. 

To Put a Gloss on Black Leather. 

Various solutions for putting a handsome and brilliant gloss on black 
leather and the methods for manufacturing them. .... 505 

CHAPTER XXXVIII. 

Sheep Leathers. 

Importance of the sheep-skin industry; Uses for which sheep-skins are 
suitable 507 

Unhairing sheep-skins; Removal of grease from raw sheep-skins . . 508 

Bating the skins; Compounds used as substitutes for hen or pigeon ex- 
crement; The Vaughn Machine Co.'s shaving and skiving machine 
for sheep-skins 509 

Imitation chamois leather 510 



XXVlll CONTENTS. 

PAGE 

White leather 511 

Cape sheep; Lining, binders and skivers; Exterior view of a sheep-skin 

tannery 512 

Tanning vats in a sheep-skin tannery; Interior view of a drying loft in a 
sheep-skin tannery; Finishing room in a sheep-skin tannery; Dressing 
sheep-skin fleshers for glove bindings, etc.; Richard Hart's process . 513 
Manasse's method for tawing sheep-skins. ...... 519 

Hibbard's process for preparing and tanning sheep-skins ; Unhairing 
composition ; Tanning composition ; Hesthal's process for dressing 
sheep-skins, etc. ........... 520 

Coloring for five dozen sheep-skins; Blue-reddish; Blue-bluish . . 522 
Cochineal; Lemon yellow; Grass green ....... 523 

Claret or maroon; Pink 524 

Solferino; Dyeing bark-tanned sheep-skins intense dull black . . 525 



CHAPTER XXXIX. 

Electric and other Rapid Tannage Systems. 

The Groth system of rapid tannage; E, Worms's process; Various pro- 
cesses for electric tannage 526 

M. C. Dizer & Co.'s experiments in rapid tannage; Other processes of 
quick tannage; S. Kas on rapid tannage; Revolution in quick tan- 
ning processes. ........... 527 

Future possibilities of quick-tanning processes. ..... 528 

Value and economy of quick-tanning processes ; Prejudice of tanners 
against testing the merits of new processes ...... 529 

Arrangement of modern tanning and currying shops .... 539 

Necessity of thoroughly cleansing the hides or skins .... 531 



CHAPTER XL. 

Bleaching Leather ; Bluing White Leather ; Bleaching Skins 
with the Hair on. 

Bleaching leather; Former process of bleaching with sulphurous acid . 532 
Bleaching chamber ........... 533 

Bleaching with solution of sulphurous acid; Apparatus for the produc- 
tion of the acid. ........... 534 

Bleaching with sodium peroxide; Bleaching with hydrogen peroxide . 535 
Bleaching with aluminium hypochlorite or magnesium hypochlorite ; 
Bleaching chamois leather; Bluing white leather .... ^36 



CONTENTS. XXIX 

PAGE 

Bleaching heavy leather; Recipe for bleaching bull's, stag's or russet 
harness leather; Recipe for bleaching leather 537 

Imparting a light color to leather ........ 588 

Agents used for toning down; Proper method of using diluted sulphuric 
acid 539 

To bleach skins with the hair on; Methods for bleaching lamb or goat 
skins intended for rugs, lap-robes, etc 540 

Use of peroxide of hydrogen and of peroxide of sodium .... 541 



CHAPTER XLI. 

Lace Leather. 

Treatment of dry Calcutta hides ........ 542 

Manipulation in the tub wheel; Stretching 548 

Stuffing; Softening 544 

Finishing; Mode of imparting a golden yellow color to lace leather ; 

Junior's method of manufacturing lace leather ..... 545 
Quick tanning process for lace and whip leather ; Bartenbach and 

Richter's process 546 

Loescher's method for manufacturing lace leather; Coupe's stretching 

machine 547 

Tidd's softening machine .......... 549 



CHAPTER XLII. 

The Dyeing of Leather. 

Hints for obtaining a uniformly colored lot with coal tar colors; Special 
adaptability of aniline colors for dyeing leather . . . . 553 

Manner of dyeing with aniline colors; Mordants and their division into 
three groups; The most important bases and the most important salts 
used in leather dyeing 554 

Soaps; Assorting the leather for dyeing; Dark brown .... 555 

Light brown; Olive brown; Cutch brown; Chestnut brown; Chocolate 
brown; Red; Alizarine red; Scarlet 556 

Ordinary red ; Dark green ; Light olive green ; Picric green ; Lemon 
yellow; Barberry yellow; Orange; Chrome yellow; Temperature in 
leather dyeing. ........... 557 

The English and Continental methods of dyeing leather; Advantage in 
paddle dyeing ; Durability of wood dyes ; Application of alizarine 
colors to chrome-tanned leather 558 



XXX CONTENTS. 

PAGE 

Indigo carmine; Young fustic; Extract of peach wood or red wood; 
Creme of logwood ........... 559 

Clearing skins preparatory to dyeing; Waterproof colors; Dimitry's pro- 
cess .............. 560 

Mordants; Minerals used as mordants; Necessity of removing an excess 
of mordanting solution; Precautions in dyeing with aniline colors . 561 

Precautions regarding cleanliness of vessels, etc. ; Manner of facilitating 
evenness of color; "Tanners' preparation" for obtaining uniform 
colored leather 562 

Bleeding or smutting off of colors 563 

The practical dyeing of leather with aniline colors; Samples dyed in a 
practical way; Sample No. I., Russia calf — combination tannage; 
Sample No. II., Russia calf — combination tannage .... 564 

Sample No. III., Glove sheep leather — Atteaux O. B. mineral tan; 
Sample No. IV., Sheep-skin — sumac tannage; Sample No. V-, — 
Atteaux O. B. mineral tan; Sample No. VI., — Atteaux O. B. mineral 
tan; Sample No. VII., India tanned goat; Sample No. VIII., Sheep- 
skin 565 

Sample No. IX., Dark green India tanned goat skin; Sample No. X., 
Pickle sheep-skin tannage — two-bath chrome; Sample No. XL, For 
i dozen sheep-skins — hemlock tannage; Sample No. XII., Goat skin 
— Atteaux O. B. mineral tan; List of aniline and alizarine colors that 
work to advantage on leather. ........ 566 

Formula for obtaining the correct ox-blood shade on combination tan 
or straight gambier tanned calf skins ....... 567 

Sample of patent phosphine leather ........ 568 

Sample of quebracho-tanned leather; Summary of the advantages of 
using quebracho; Calf leather dyeing 569 

List of leather dyes . . . . . . . . . . 570 

The dyeing of leather for shoes; Process for preparing tanned calfskins 
for dyeing ............ 571 

Dyeing calfskins for shoe work; Colors for any shade of brown . . 572 

Varieties of colored leather used for shoes; Directions for obtaining cor- 
rect ox-blood shade on one dozen chrome-tanned calf skins. . . 573 

Methods of dyeing leather used in Germany; Preparing the dye bath . 574 

On what the depth of a certain color is dependent ; Preparation of a 
mordant of tin-salt . . . . . . : . ... 575 

Difficulty of always obtaining a definite tone of color; Use of solutions 
of coloring matters of an exactly determined concentration ; Theory 
of solutions . . . . • . . . . . . . . 576 

Best method of effecting dilution ; Preparation of a sample scale of 
leather 577 

Working with ready-made dye-stuffs; Toning fluids; Mode of action of 
toning fluids 578 

Preparation of toning fluids 579 



CONTENTS. XXXI 

PAGE 

The color mixtures; Directions regarding the respective proportions for 
the different kinds of leather; Genuine Russia leather .... 580 

Morocco leather; Cordovan leather; Chamois leather; Tawed leather . 581 
The proper selection of dye-stuffs ; The most important dyes of the 
group of the aniline colors ; Colors for pure colors without toning ; 
Coloring matters for colors formed by mixing two coloring matters . 583 
Blended colors; Use of aniline colors besides wood colors; Preparation of 
the leather for dyeing . . . . . . . . . . 584 

Sorting; Principal point to be observed in sorting morocco and cordovan 
leather; The most difficult task in sorting tawed leather; Separation 
of the skins into several classes ........ 585 

Washing the skins ........... 586 

The object of washing; Mechanical pressure in washing; Treading the 
skins. ............. 587 

The washing machine. .......... 588 

Time required for washing. ......... 591 

Rules in reference to washing leather ....... 592 

Quality of the water; Importance of the chemical constitution of the 
water ............. 593 

Forster's sandstone filter for filtering turbid water ..... 594 

Nourishing 595 

Nourishment of fine glace leather; Operation of nourishing . . . 596 
Preservation of yoke of egg; Lanolin. ....... 597 

Dyeing tawed leather (glace" leather); Dipping process .... 598 

Dipping apparatus 599 

Manner of operating the apparatus ........ 600 

Dyeing upon the board; Utensils required; The dyeing table or board; 

Arrangement of the fluids required in dyeing; The operation of dyeing. 601 
Avoidance of the formation of stains ; Action of the mordant with the 

use of vegetable dye-stuffs; Working with aniline colors . . . 602 
Dyes and toning fluids; Proper use of aniline colors and of indigo car- 
mine 603 

Aniline colors for colors of a pure tone; Aniline colors for dyeing glace" 
leather for fancy goods ; Directions for the production of blended 
colors upon glace leather; Tight ochre yellow and maize yellow . 604 
Dark gold color to umber; Wood brown to mahogany color; Reddish 
brown to Venetian red; Brownish red (Pompeian red); Pure Havana 
brown; Sienna brown; Dark bister brown ...... 605 

Olive; Red brown to dark brown; Green brown to dark brown; L,ac 
brown and dark brown; Sepia brown; Iron violet; Gray blue (dark 

pigeon gray) 606 

Slate gray; Iron or steel gray; Tight ash gray; Toning fluids for the dif- 
ferent broken colors .......... 607 

Mixed colors; Definition of the term; Dyeing with mineral colors . . 608 
Dyeing leather black 609 



xxxii CONTENTS. 



Dyeing with tannin and iron salts; Dyeing with logwood and potassium 

chromate 610 

Dyeing with tannin and logwood 611 

Deep black nigrosin color; Blue black nigrosin color; Glazing and gloss- 
ing of leather; Glazing; Preparation of the glazing fluid . . . 612 

Application of the glazing fluid. 613 

Glossing; Preparation of a glossing mass; Glossing rolls . . . . 614 
Use of vaseline and by-products of the tar industry for rendering the 

leather pliable and for glossing; Glazing rolls 615 

Dyeing rabbit skins black 616 

APPENDIX. 

Method of coloring chrome-tanned leather; Wm. M. Norris' patent . 617 

Art of tawing hides or skins; Wm. M. Norris' patent .... 618 

Borax * 622 

Anthrax 629 

Degras 630 

American degras from wool waste 631 

The per cent, of water in degras 632 

Tanning matters and their determination 633 

Electric transmission of power 636 

To dress strap, pocket book, bag, case and welt leather and flexible 

splits 637 

List of patents relating to the manufacture of leather, issued by the gov- 
ernment of the United States of America, from January i, 1884, to 

August 31, 1897 639 

Index . . . - . . 655 



THE MANUFACTURE OF LEATHER. 



CHAPTER I. 

WATER AND PUMPS. 



Tanneries and currying shops are not, in the United States, 
located, as a rule, upon rivers and streams, as they are in many 
parts of Europe. There are advantages in being located upon 
rivers and streams, in having at nearly all times a uniformity in 
the hardness or softness of the water ; but there are also disad- 
vantages in the great variations of its temperature. The idea 
in the United States is to have the tannery or currying shop 
located upon a railroad switch, so as to have easy and cheap 
communication with all parts of the country, and hence the 
softness or hardness of the water is made a minor detail. If 
hard, it takes more tan bark or extract to do the tanning than 
if it were soft, and more dyeing materials to do the coloring. 

However, water occupies an important position in tanning, 
it being employed, on the one hand, for washing, cleansing, 
and preparing the raw hides, and on the other, as a solvent for 
all the tanning materials and as a diluent for all the coloring 
and dyeing materials used. 

We shall here briefly discuss the most important admixtures 
of water, and their influence in tanning. 

Ail naturally occurring water contains smaller or greater 
quantities of alkaline and earthy alkaline salts, and carbonic 
acid in solution. There is no entirely pure well or river water, 
i. e., free from all admixtures. By leaving out of consideration 
the small quantity of ammonium nitrite, organic substances, 

( i ) 



2 THE MANUFACTURE OF LEATHER. 

etc., held in solution by rain water, the latter might be consid- 
ered chemically pure water. 

Water is distinguished as hard and soft, according to the 
quantity of earthy alkaline salts it contains, the amount of min- 
eral substances varying from I milligrm. to I grm. per litre. 
The principal admixtures occurring in water are, as mentioned 
above, the alkalies, such as potassium, sodium, alkaline earths, 
lime, and magnesia ; the oxides of a few heavy metals in com- 
bination with ordinary mineral acids, sulphuric, nitric, phos- 
phoric, carbonic, and hydrochloric acids. The gases held in 
solution are chiefly carbonic acid and atmospheric air, sulphide 
of hydrogen occurring but seldom. 

The admixtures of spring and well water consist principally 
of the constituents of the layers of earth through which it per- 
colates. Those, for instance, contained in the waters flowing 
through the dolomitic stratification may be considered as pure 
solutions of the dolomitic rock, consisting as they do of calcium 
carbonate, magnesium carbonate, and silicic acid, the quantity 
of all other constituents being so small as to make it almost 
impossible to determine them by quantitative analysis. The 
waters percolating through the basalt and the new red sand- 
stone contain principally calcium carbonate, magnesium car- 
bonate, silicic acid, considerable quantities of free carbonic 
acid and small quantities of common salt, calcium sulphate, and 
sodium carbonate. The total dry residue of waters coming 
from the lias formation varies between 268 and 516 milligrms., 
the principal constituents being in this case also calcium car- 
bonate, 200 to 400 milligrms. per litre, magnesium carbonate 
(varying from 30 to 90 milligrms. per litre), sodium carbonate, 
free carbonic acid, etc. 

Besides these natural constituents, spring and well water, but 
especially the latter when in large cities or in the neighborhood 
of dumping places for all kinds of offal, the soluble substances 
of which percolate through the soil, contain frequently in solu- 
tion organic products of decomposition of organized bodies 
such as bacteria, fungi, alkaline nitrates, especially ammonia, 



WATER AND PUMPS. 3 

and alkaline salts. Though such water, for hygienic reasons, 
is generally unfit for drinking purposes, it may be put to tech- 
nical use. 

In determining the qualities of water for tanning purposes, 
two points, as mentioned, must be taken into consideration, 
viz., first, the behavior of the water when used as a solvent for 
the tanning materials, and second, whether it is adapted for 
preparing the hides for tanning. If the water is to be used for 
dissolving or extracting tanning materials containing tannic 
acid, the earthy alkalies, lime and magnesia combinations, exert 
a decidedly injurious effect, as, by forming insoluble combina- 
tions with the tannic acid, they render a part of the tanning 
material ineffective. If the water is to be used for soaking, 
cleansing, and washing the hides, mineral admixtures may exert 
a favorable influence. In speaking of the chemical properties 
of the skin tissue and the coriin, it will be shown that some of 
the alkaline salts exert a dissolving influence upon the intercel- 
lular substances or coriin, the effect of small quantities of alka- 
lies being an increased solution of cori'in in acids. From this 
we may draw the conclusion that hard water promotes the 
soaking of dried hides, but that a part of the coriin is with- 
drawn from the skin tissue if the hide is too long subjected to 
the action of the water.* 

Hides intended for sole leather are swelled ox "plumped" in 
order to cause them to be better adapted to the absorption of 
the tanning material. In case the natural swelling is not suffi- 

*Eitner (see Der Gerber, 1877, No. 178, and Dingl. Polyt. Journ., ccxxiv, 524) 
has made experiments as regards the effect of different inorganic constituents of 
water upon the depilated skin, using various solutions of alkaline, calcium, and mag- 
nesium salts in distilled water. He found that water containing only calcium chlor- 
ide and magnesium chloride had almost no swelling effect, and distilled water 
scarcely any, it being further remarked that carbonic acid, and consequently water 
containing bicarbonates, exerted a swelling effect upon the hide. Alkaline chlorides 
and alkaline earths, such as magnesium chloride, potassium and sodium chlorides, 
have no swelling effect whatever, even nullifying it partly. Calcium and magnesium 
sulphates proved the best swelling materials for hides, this explaining the advantage- 
ous effect produced in swelling by a careful addition of sulphuric acid to water con- 
taining much bicarbonate. 



4 THE MANUFACTURE OF LEATHER. 

cient, it is assisted by the use of inorganic as well as organic 
acids. This swelling process is accelerated, and the falling back 
of the hides into their previous state prevented by the use of 
hard water. 

Soft water is preferred for the manufacture of upper leather, 
since the hides must not be swelled so much as those for sole 
leather, as otherwise the smooth cut would be injured. 

The temperature of the water used for preparing the hides 
must also be taken into consideration. Generally speaking, the 
water should be as cold as possible for the manufacture of sole 
leather to prevent the skin fibre from being softened too much. 

It is also of importance that the water should not be exposed 
to too great variations in temperature in summer and winter ; 
46 to 50 F. may be designated as the most favorable temper- 
ature. Spring water coming from deeper strata of the soil, and 
possessing consequently a more even temperature, is to be pre- 
ferred to river water. 

As regards the chemical examination of water, we refer the 
reader to the following 

METHODS FOR DETERMINING THE CONSTITUENTS OF WATER. 

We cannot enter upon a description of the different qualita- 
tive and quantitative methods of determining the constituents 
of water; but will only briefly describe a few examinations 
of importance in tanning, and those who may desire a full 
description of the methods and apparatus employed, are re- 
ferred to the treatises of Wanklyn and Frankland on Water 
Analysis. 

The qualitative examinations of water as to its admixtures of 
lime, magnesia, alkalies, chlorine combinations, sulphuric and 
carbonic acids, the larger or smaller quantity of which gener- 
ally determines its character, can be executed in the following 
manner: 

1. The chlorine combinations are shown by the formation of 
a white precipitate when treated with nitrate of silver in nitrate 
solution. 



WATER AND PUMPS. 5 

2. Sulphuric acid and sulphates are recognized by the for- 
mation of a white precipitate with barium chloride. 

3. Carbonic acid is present when the addition of clear lime- 
water gives a white precipitate. 

4. The presence of silicic acid, lime, and magnesia, by evap- 
orating to dryness with an addition of hydrochloric acid in a 
platinum dish of a capacity of about one litre. The residue is 
taken up with hydrochloric acid and water, the portion remain- 
ing undissolved being silicic acid. The lime can be separated 
as calcium oxalate from the filtrate with ammonium oxalate. 
After removing the calcium oxalate by filtration and evapora- 
tion of the filtrate, the magnesia is precipitated with ammonium 
phosphate as ammonium magnesium phosphate. 

5. Organic substances are shown by adding a few drops of 
potassium permanganate and some pure sulphuric acid. If 
organic substances are present, the potassium permanganate, 
added drop by drop, is decolorized until all the organic sub- 
stances are completely oxidized. 

6. Determination of the entire residue. One litre is carefully 
evaporated to dryness, requiring from twenty-four to twenty- 
six hours, in a platinum dish, the weight of which has been 
previously determined. The residue is dried at 356 F. until 
a decrease in weight no longer takes place. 

7. A determination of hardness with alcoholic soap solution 
serves in most cases for tanning purposes as a substitute for a 
quantitative analysis. We give, therefore, a short description 
of it. 

The process of determining the hardness of water by a soap 
solution of a determined percentage, which was introduced by 
Clark, is a very simple one. By an addition of soap solution 
toswater containing too much lime or magnesia, a white preci- 
pitate of lime or magnesia soap insoluble in water is formed as 
long as calcium or magnesium salts are present. When an ex- 
cess of soap solution has been added, the end of the reaction 
is indicated by the formation of lather on shaking the fluid. 

The effective value of the soap solution is determined by 



6 THE MANUFACTURE OF LEATHER. 

testing it with a lime solution of a determined percentage. 
Clark's method is, according to Faisst and Knauss, executed in 
the following manner: — 

The soap solution required for titration is obtained by dis- 
solving 30 grms. of dried soda soap in 3 litres of alcohol of 90 
per cent. The turbid solution is filtered and preserved for use. 
200 grms. of this concentrated solution are first compounded 
with 150 grms. of water (in order to reduce the alcohol to the 
strength of 56 Tralles, which has been proven to be the most 
suitable), and then with J 30 grms. of spirit of wine of 56 
Tralles. 45 c.c. of the solution thus obtained are required for 
the precipitation of 12 milligrams, of lime in 100 c.c. of water. 
The exact titre of this solution must be further determined and 
corrected by adding concentrated soap solution, or alcohol of 
56 Tralles, so that 12 milligrms. of lime require exactly 12 
milligrms. of soap solution. For the determination of the con- 
centration of the soap solution a neutral solution of calcium 
chloride is used, which is obtained by dissolving 0.214 g rm - of 
calcium carbonate in hydrochloric acid, evaporating the solu- 
tion, and dissolving the residue to 1 litre. 100 c.c. of this 
solution contain 12 milligrms. of calcium oxide, or an equiva- 
lent quantity of calcium chloride. With this solution the soap 
solution is tested, and the latter sufficiently diluted, so that 
exactly 45 c.c. are required to produce, when brought together 
with 100 c.c. of lime solution, and shaken, a white lather re- 
maining for about five minutes. 

The process of determining the hardness is as follows : A 
distinction is made between "total hardness" and "permanent 
hardness." The hardness of water not heated is called "total 
hardness," and the hardness produced by the earthy sulphates 
is termed "permanent hardness," because unaffected by ebulli- 
tion ; the term "temporary" or "changeable hardness," is 
also frequently used to denote the hardness produced by the 
earthy carbonates, because removable by ebullition. 

1. Determination of Total Hardness.— \oo c.c. of water are 
measured with a pipette into a test tube, having a capacity of 



WATER AND PUMPS. 7 

200 c.c, and provided with a ground glass stopper. Water 
containing much lime is previously diluted with distilled water, 
so that to a determined number of cubic centimeters (10, 20, 
or 30) of the water to be tested, 90, 80, or 70 c.c. of distilled 
water are added. A mark on the tube indicates the point to 
which it is filled by IOO c.c. of the fluid. 

Before adding the soap solution, the free carbonic acid is 
partly removed by shaking the water. 

As most well waters have more than 12 of hardness, only 
10 c.c. of the water to be tested are measured off, and diluted 
to the mark with distilled water. Titrated soap solution is 
then slowly added from a burette until, after vigorous shaking, 
a dense delicate lather is formed which will hold for about five 
minutes. The soap solution is first added in half cubic centi- 
meters and later on in drops. The shaking must always be 
done in the same manner, and the volume of the fluid amount 
to 100 c.c. before the soap solution is added. Should a second 
experiment be necessary, the same quantity of water is used, 
or, in case but little soap solution has been consumed for the 
diluted water ( 10: 100), correspondingly more (25 to 50 c.c), 
so that the quantity of soap solution, which should previously be 
approximately calculated, does not exceed 45 c.c. With the 
assistance of the following table, the respective degree of hard- 
ness which, in case the water has been diluted, must be multi- 
plied with the corresponding figure, is found from the cubic 
centimeters of soap solution consumed. (The corresponding 
figure is found by dividing 100 by the cubic centimeters used 
for the experiment.) 

3.4 c.c. soap solution consumed 0.5 degree of hardness. 

5.4 " " " 1.0 " " 

7-4 " " " 1.5 

9.4 " " " 2.0 " " 

The difference of 1 c.c. of soap solution = 0.25 degree of 
hardness. 



THE MANUEACTURE OF LEATHER. 



1 1.3 c.c. soap solution consumed 2.5 degree of hardness. 



13.2 

17.0 
18.9 
20.8 



3-o 

3-5 
4.0 

4-5 



The difference of 1 c.c. of soap solution = 0.26 degree of 
hardness. 

22.6 c.c. soap solution consumed 5.5 degree of hardness. 

24.4 " " " 6.0 

26.2 " " " 6.5 

28.0 " " " 7.0 

29-8 " " " 7-5 

31.6 " " " 8.0 

The difference of 1 c.c. of soap solution = 0.277 degree of 
hardness. 

33.3 c.c. soap solution consumed 8.5 degree of hardness. 



35 -o 
36.7 
38.4 
40.1 
41.8 



9.0 

9-5 
10.0 
10.5 
1 1.0 



The difference of 1 c.c. of soap solution 
hardness. 



0.294 degree of 



43.4 c.c. soap solution consumed 11.5 degree of hardness. 

45.0 " " " 12.0 " " 



The difference of 1 c.c. of soap solution = 0.31 degree of 
hardness. 

Suppose 50 c.c. of the water to be tested had been placed in 
the test tube and diluted with 50 c.c. of distilled water, and had 
consumed 22.6 c.c. of soap solution for the formation of lather. 
According to the table these 22.6 c.c. of soap solution corre- 
spond to 5.5 degrees of hardness. This figure 5.5 is multiplied 
by 2, which gives 11 as the actual degree of hardness of the 
water. (The figure 2 is obtained by dividing 100 c.c. by 50 
c.c.) 



WATER AND PUMPS. 9 

2. Determination of Permanent Hardness. — For the determi- 
nation of the permanent hardness 500 c.c. of water are boiled 
in a sufficiently large matrass for at least one and a half hours, 
a part of the evaporated water being replaced by distilled water. 
The boiled water, when cold, is poured into a flask having a 
capacity of 500 c.c, and the matrass rinsed out with distilled 
water, the rinsings being added to the water in the flask. The 
latter is then filled with distilled water up to the mark, and the 
entire contents filtered through a dry filter into a dry test tube. 
The degree of hardness of a definite number of cubic centime- 
ters is then determined in the above manner. 

Clark was the first to introduce the term " degrees of hard- 
ness," 1 degree corresponding, according to him, to 1 part 
(grain) of calcium carbonate or its equivalent of another cal- 
cium salt, or equivalent quantities of magnesia or magnesium 
salts in 70,000 parts (=1 gallon) of water, At the present 
time 1 degree of hardness is suitably estimated as equal to 1 
part of calcium oxide in 100,000 parts of water. The German 
degrees of hardness are reduced to English by multiplying the 
degrees found by 5 and dividing by 4, the reduction of English 
to German degrees being vice versa accomplished by multiply- 
ing by 4 and dividing by 5. In France 1 degree of hardness is 
calculated as equal to 1 part of calcium carbonate in 100,000 
parts of water, 1 degree of hardness being therefore : 
In Germany = 10 milligrams of calcium oxide in 1 litre of water. 
In France = 5.6 milligrams of calcium oxide in 1 litre of water, 

or an equivalent quantity of magnesia or magnesium 

salts. 

SOFTENING WATER. 

There have been proposed numerous methods for softening 
and purifying water. Some effect a chemical reaction, others 
act by a mechanical process, while others, such as oak sawdust, 
act both chemically and mechanically ; the tannic acid which it 
contains forming tannates of lime and magnesia by the decompo- 
sition of the carbonates, and these tannates, on account of their 
low specific gravity, float about the water. The sulphates and 



IO THE MANUFACTURE OF LEATHER. 

chlorides are prevented from agglutinating into a crust by the 
mechanical action of the sawdust. Such anti-incrustation 
remedies as oil-cake, potatoes and other starch)'' matter, glue, 
offal of hoofs and horns, tobacco juice, Irish moss, peat, tow, 
hemp, etc., envelop the particles of lime and deposit them in 
the form of sludge. 

Clay also precipitates the lime salts in the above manner. 
Tannic acid does not act upon sulphates and chlorides, neither 
is sulphate of lime altered by acetic acid, the action of both 
these acids being to convert the carbonates into soluble ace- 
tates, and of course in this action both tannic acid and acetic 
acid are absorbed and the work which they might do in the tan 
pit is lessened. Both tannic and acetic acids are employed to 
purify water, but the employment of these acids is expensive, 
and their place can be taken by cheaper acids and alkalies. 

Borax is the best agent that can be used for purifying water 
for the use of tanners and curriers. Its price is now about $}4 
cents a pound, and 5 or more pounds of borax will soften one 
thousand gallons of water, such as is used by the average tan- 
ner. Some harder waters will require a little more borax, and at 
the present price of hemlock and oak bark, will save him on an 
average about $1.50, that is, the tanner by buying about 
twenty-five cents worth of borax will be $1.50 in pocket. 

To soften one thousand gallons of water 5 pounds of borax 
are used. It is dissolved in boiling water and poured into the 
vat or tank under vigorous stirring. 

The laundry men have tried all sorts of chemicals for soften- 
ing the water which they use for washing clothes, and they 
have found none so harmless, cheap and effective as borax. 
The large packers of this country have tried all sorts of chem- 
icals for preserving their meats, but are now using borax be- 
cause of its cheapness and preserving qualities. 

The foregoing are two reasons why the tanners of all kinds of 
hides and skins should use borax in their soaks, as the soaks are 
thus kept fresh and prevented from becoming putrid or foul, with 
the consequent withdrawing of valuable gelatine from the hide or 



WATER AND PUMPS. II 

skin under treatment. By the use of borax in the soaks a firmer, 
heavier and more solid leather can be produced by this saving of 
gelatine. In the leaches borax is equally invaluable for soften- 
ing the water before it goes on the tan bark, because of the 
large saving of money which it effects. Of course the tannic 
acid will soften the water, but the hardness of the water has to 
be overcome by the tannin before the water itself can become 
effective. 

Borax is one of the gentlest of the alkalies and is one of the 
most perfect of the cleansers. It will clean a hide or skin thor- 
oughly, which is a most desirable point in tanning, and by ren- 
dering the water soft it will act upon the tan bark quickly under 
any system of leaching. 

Borax is largely used by dyers and colorers of leather for 
rendering the water soft and also as a mordant, and thus pre- 
venting the absorption of too much coloring matter or dry stuffs, 
and giving a more uniform color and lustre. 

Borax is very largely used by the manufacturer of glazed kid, 
not only in soaking and cleansing the skin, but it is a fine mor- 
dant and gives a uniform color to the skins. It is well known 
that in the treatment of colored goods in the laundry, borax 
is used in the water to prevent the colors from running ; it fixing 
them. Borax has heretofore been a little too high in price to 
be generally used by the tanner or currier, but now the price 
has fallen so low as to bring it within his reach, and he should 
improve his opportunity. 

It was formerly imported from abroad, but since the discov- 
eries of this substance on the Pacific Coast nearly all the borax 
used in this country comes from there, and as a consequence 
the price has fallen to its present low point. 

A clean hide or skin will tan more quickly than a dirty one, 
hence borax will hasten the tanning process and thus save time 
and money. 

It is to be observed that water evaporates at all temperatures, 
and its solvent properties far exceed those of any other known 
liquid. The softer the water the greater its solvent properties. 



12 THE MANUFACTURE OF LEATHER. 

A very large proportion of all the different salts are more or 
less soluble in it, the solubility increasing generally as the tem- 
perature rises, so that a hot, saturated solution deposits crystals 
on cooling. There are a few exceptions to this rule, one of the 
most remarkable of which is common salt, the solubility of 
which is nearly the same at all temperatures, the hydrate of 
lime (slaked lime) being more soluble in cold than in hot water, 
sulphate of lime being also less soluble in hot than in cold water, 
and insoluble at 302 F., or between 284 and 302 F. 

Water is one of the most potent agencies with which the 
tanner has to deal, and the harder the water the less profit 
there will be in the tanning and currying industries. 

PUMPS. 

The methods of obtaining water in tanneries vary greatly, 
and we will here enter briefly into the subject of pumps. 

There is no mention made in history of pumps prior to the 
year 200 B. C. The Chinese cannot claim any priority in this 
special branch, which is peculiar, when we consider their 
manner of irrigation. A pump is a rarity with them. 

A tanner's pump is not a very intricate machine, and its parts 
are comparatively few. But its action, or want of it, sometimes 
makes it seem most mysterious. To those readers who have 
not considered the question of water dispensation, the remark 
that pumping machinery stands prominent among the various 
branches of engineering may seem to allow of discussion. A 
few instances will very soon give ample proof. How could our 
coal be obtained and our mines worked, if not for the pumping 
plant? — our water supply obtained, or our sewage and chem- 
ical works carried on? When man enters Nature's store-house 
in search of wealth, he finds water ever ready to dispute his 
supremacy ; it may be in a constant stream, varying only with 
the season ; oftentimes vast quantities are stored in crevices of 
the rocks. Some idea of the quantity of water raised will be 
given when it is known that often its weight is double and 
treble that of other material raised, and is frequently 30 per 
cent, in coal mines. 



WATER AND PUMPS. 1 3 

Rude nations have not possessed the machine, simple as it 
is, but have always resorted to a more laborious method to ob- 
tain water. In the early ages it does not appear to have been 
known to the Greeks or Romans. Although the pump was 
invented 200 B. C, it was not until the beginning of the seven- 
teenth century that its true principles were understood ; al- 
though in 1636 fire engines were built in Holland, and from 
which, as far as general principles are concerned, no improve- 
ments have been made. 

The pumps commonly used for raising water from wells may 
be divided into two classes — lifting pumps and forcing pumps. 
The lifting pumps may be again subdivided into two varieties, 
namely, those with a hollow piston and those with a solid or 
plunger piston. 

Lifting pumps with a hollow piston, called also atmospheric 
pumps. This variety, in its simplest form, consists of the fol- 
lowing parts : 

A cylinder or tube, in which is fixed a valve opening upward, 
and above which works a piston provided with a valve also 
opening upward. The part of the cylinder in which the piston 
works is called the body of the pump, and is the only part 
which need be bored with any great accuracy. The top of the 
cylinder may be opened or closed, it matters not which, but 
somewhere above the level to which the piston ascends there 
must be an orifice for discharging the water. 

The action of the common atmospheric pump is so simple, 
and is so well known to every school boy, that it will be un- 
necessary here to dwell upon it. The cylinder is made of vari- 
ous materials, as wood, iron, or copper, and frequently the 
lower part below the fixed valve is a mere iron pipe furnished 
with a strainer at its lower extremity. The fixed valve in this 
kind of pump must be placed at such a level that the depth 
from it to the surface of the water in the well must never ex- 
ceed the height of a column of water which will balance the 
atmospheric pressure or weight of the atmosphere. This 
weight is measured in the barometer by a column of mercury, 



14 THE MANUFACTURE OF LEATHER. 

which varies in different parts of the world, and at different 
altitudes, from 28 to 31 inches. Thus, an atmospheric pump 
at the level of the sea may have its fixed valve several feet 
higher than a similar pump working on the top of a high 
mountain. The height at which the mercury stands in a 
barometer at any given place affords, in fact, a tolerably prac- 
tical measure of the height to which water will rise in a vacuum 
when pressed by the external atmosphere. Thus, in theory, 
where the mercury stands in the tube of a barometer at a 
height of 30 inches, the sucker or fixed valve of an atmospheric 
pump may be placed 30 feet above the surface of water in a 
well. In practice, however, owing to imperfection of materials, 
fluctuations of level in the water, and other causes, this differ- 
ence of level is too great, and should not really exceed 25 feet. 
In shallow wells, therefore, which are not more than about 27 
feet in depth, the part of the cylinder or pump above the fixed 
valve need never exceed the length of the slope or space 
through which the piston works. In deep wells the ascending 
part of the cylinder above the body of the pump in which the 
piston works may be, theoretically, of any height. There are 
difficulties, however, connected with the valves in the movable 
piston which render it inconvenient to have the lift in this kind 
of pump much more than 100 feet. Whatever may be the 
height of the column of water above the movable piston, it is 
evident that the absolute weight of this whole column has to be 
lifted at each stroke of the piston, and for this reason atmo- 
spheric pumps, which are worked by hand, have scarcely any 
of the pump above the piston, as otherwise the weight of water 
to be lifted at each stroke would be too great for the power to 
be applied. This practically limits the height to which water 
can be raised from wells by common atmospheric pumps 
worked by hand to about 25 feet. 

In deep wells, however, when pumps are worked by horse or 
steam power this objection does not apply, and if the power be 
sufficient to raise at each stroke the whole column of water 
above the piston, the length of the cylinder above this piston 



WATER AND PUMPS. I 5 

is only limited by the practical considerations before alluded to 
in connection with the valves. It should be observed that the 
common atmospheric pump is seldom or never used in water- 
works for the purpose of raising water. 

In the manufacture of waxed-calf, it is important that there 
should be a uniform temperature of the water in which the 
skins are soaked, and but few of the best manufacturers of this 
class of leather in France or Germany soak the skins in run- 
ning water, because it is extremely cold in winter and warm 
in summer. In default of water from a live source, it may 
be drawn from a cistern ; but, it may be said, it requires a 
large quantity of water, and that it will be costly to draw it 
to the surface. But it is very seldom that a tannery does not 
possess a horse or a steam engine ; the horse is often idle in 
the stable ; the engine has always a little power to spare above 
its requirements ; or by means of the simplest machinery a 
double-action pump may be constructed and made to work by 
horse or steam power, and in this way there can be obtained 
from 2,000 to 2,500 gallons per hour or more if desired. There 
should be in the centre of the tannery or in one of the corners, 
a large tank raised at least six feet above the ground ; the 
water, pumped into the tank, can be distributed at will over the 
whole establishment. The total expense may amount to $500 
or $600 ; and such a figure is not large in consideration of the 
importance of the result : to have always at disposal a quantity 
of pure water and of an equal temperature. 

If the tannery is a large one, and requires more water than 
can be furnished by this simple outfit, then, in our opinion, the 
tanner can not do better than to follow the example of the 
American Oak Leather Company, of Cincinnati, Ohio, and the 
Henry Lang Co., patent leather manufacturers of Newark, 
N. J., who have recently put in a pump with a pipe about 200 
feet deep, for pumping water by compressed air by the Pohle 
system. 

Tanners and those interested in mining and hydraulics will 
be glad to have some account of the Pohle system of raising 



i6 



THE MANUFACTURE OF LEATHER. 



water from non-flowing wells, mines, etc., which has been intro- 
duced by the Ingersoll-Sergeant Drill Company, of No. 26 
Cortlandt street, New York, N. Y. 



Fig. 1. 





gj^'j? 



The following description is given by the makers : 
The pump proper, shown in Fig. 1, consists of only 
two plain open-ended pipes, the larger one with an 
enlarged end piece constituting the discharge pipe, 
and the smaller one let into the enlarged end piece 
of the discharge pipe constitutes the air inlet pipe, 
through which the compressed air is conveyed to 
the enlarged end piece to the under side of the 
water to be raised. No valves, buckets, plungers, 
rods or other moving parts are used within the pipes 
or well. 

In pumping, compressed air is forced through the 
air pipe into the enlarged end at the bottom of the 
water pipe, thence by the inherent expansive force 
of the compressed air, layers or pistons of air are 
formed in the water pipe, which lift and discharge 
the water layers through the upper end of the water 
discharge pipe. At the beginning of the operation 
the water surface outside of the pipe and the water 
surface inside of the pipe are at the same level ; hence the ver- 
tical pressures per square inch are equal at the submerged end 
of the pipe, outside and inside. As air is forced into the lower 
end of the water pipe, it forms alternate layers with the water, 



WATER AND PUMPS. 1 7 

so that the pressure per square inch of the column thus made 
up of air and water, as it rises inside of the water pipe, is less 
than the pressure of water per square inch outside of the pipe 

Owing to this difference of pressure, the water flows contin- 
ually from the outside to within the water pipe by gravity force, 
and its ascent through the pipe is free from shock, jar or noise 
of any kind. 

These air sections or strata of compressed air form water- 
tight bodies, which, in their ascent in the act of pumping, per- 
mit no " slipping " or back flow of water. As each air stratum 
progresses upward to the spout, it expands on its way in pro- 
portion as the overlying weight of water is diminished by its 
discharge, so that the air section, which may have been say 50 
pounds per square inch at first, will be only 1.74 pounds when 
it underlies a water layer of four feet in length at the spout, 
until finally this air section, when it lifts up and throws out this 
four feet of water, is of the same tension as the normal atmo- 
sphere ; thus proving that the whole of its energy was used in 
work, and that this pump is a perfect expansion engine. 

As the weight of the water outside of the discharge pipe (the 
head) is one-third greater per square inch than the aggregate 
water sections within the pipe when in operation, it follows that 
the energy due to this one-third greater weight is utilized in 
overcoming the resistance of entry into the pipe, and all the 
friction within it. 

The Pohle "air lift" pump gives ninety per cent, of efficiency 
from the air receiver in water pipes of large diameter, and as 
a rule, above eighty per cent. It retains this efficiency with- 
out repairs, or until the pipes rust through, whereas ordinary 
bucket and plunger pumps gradually lose efficiency from the 
first stroke they make, and lose it rapidly if the water contains 
sand or is acid in character. It has been estimated by compe- 
tent experts, that under favorable conditions and large diame- 
ters of water and air pipes, 1,000,000 gallons of water can be 
raised 100 feet high with one and a half tons of good coal. 

The air reservoirs are all strongly made of homogeneous 
2 



1 8 THE MANUFACTURE OF LEATHER. 

steel, tested and guaranteed at working pressures of no 
pounds ; they are provided with the proper openings for inlet 
and outlet pipes, manhole and head, drain cocks, pressure gage 
and safety valve. 

As the pump has no valves, no standing water remains in the 
pump column after the operation of pumping ; it recedes into 
the well, and there is none left to freeze in cold weather. The 
capacity of the pump is unlimited, and with the proper propor- 
tions of air to the water, will work efficiently in pipes several 
feet in diameter. Estimates have been made which indicate 
that a thirty-inch pipe will deliver 16,660 gallons per minute, 
equal to 1,000,000 gallons per hour. 

Experience has proved that by the use of this constant upward 
flow of water, artesian wells have been freed from their accumu- 
lated sedimentary deposits, as well as that lodged in the fissures 
and crevices of their wall rock, and have been thus made to 
yield greater quantities of water than they ever did before. For 
chemical uses, and for the liquids of the arts, there is no super- 
ior method to the "Air Lift." It is used successfully for rais- 
ing sulphuric acid of high specific gravities, and is well adapted 
for ore leaching works, vinegar works, sugar refineries, dye 
works, tanneries, paper pulp works, etc. 

This pump can be run with motor, water wheel, steam, oil or 
gas engine, or, any other source of power. 

It makes a much greater difference in the manufacture of 
waxed-calf than with any other class of leather, whether the 
water is hard or soft ; still some prefer it soft, as it contains less 
calcareous substances than hard water, which is, as we have 
explained, often saturated with earthy salts. We have not at- 
tempted to give in this work the analyses of all the waters that 
trickle through our soil; it is the tanner's business to become 
acquainted with the quality of the water he has at his disposal, 
and to utilize it according to the elements it contains. Study 
the water ; if it is soft the soaking will be done promptly, if it 
is hard it will take longer; but, any way, there is a certainty of 
arrriving at the same result; that is the aim. 



WATER AND PUMPS. 



19 



Fig. 2 illustrates a Pohle Air Lift Plant at the works of the 
Henry Lang Co., Patent Leather Manufacturers of Newark, 
N. J. It has recently been installed, and is giving entire satis- 
faction. The owners of the plant are enthusiastic over the work 
it is accomplishing. Its normal work is 10,000 gallons of water 



Fig. 2. 




DISCHARGE PIPE AND WATER TANK OUTSIDE OF HENRY LANG CO.'S FACTORY. RAISING 
WATER BY THE POHLE AIR LIFT. 

every hour. The outfit comprises an Ingersoll-Sergeant Class 
"F" Air Compressor, an Air Receiver, and the Pohle device in 
the well. The total depth of the well is 204 feet; diameter, six 
inches. The water level is twenty-five feet beneath the surface. 
The total lift from the level in the well to the tank is eighty-five 
feet. There is a steady supply of water. 



20 THE MANUFACTURE OF LEATHER. 

When the conditions that surround other pumping outfits are 
compared with the simplicity of the Pohle Air Lift method, the 
differences are vast in favor of the latter. This plant replaced 
a deep well pump which failed to give the necessary supply of 
water. In the illustration, Fig. 2, the view shows that the dis- 
charge pipe is exposed to all sorts of weather. That, however, 
is no disadvantage to the Pohle Air Lift Pump, because when 
the pump is not in operation the water does not stand in the 
pipe, but falls back into the well, thus obviating the danger of 
freezing, rust, or other detrimental effects. 

• For a factory, tannery, brewery, paper-mill, or other estab- 
lishments, the plant described can be installed at a reasonable 
outlay. The owners of this plant say in a letter that it is the 
best pump ever brought to their notice, and that it far exceeds 
their expectations. 



CHAPTER II. 

ANIMAL SKIN. 

In the production of leather there are two classes of raw pro- 
ducts with which the tanner has to deal ; they are — 

i. Hides and skins to be converted into leather, and 
2. Materials by the aid of which the conversion or tan- 
ning is effected. 

The object of the present chapter is to explain the structure 
of the skin and its behavior with reagents, without which 
knowledge an intelligent prosecution of the art of tanning is 
rendered difficult and at times hazardous. 

The structure of animal skin consists of several readily dis- 
tinguishable layers, which behave differently in a chemical as 
well as in a physical respect. 

The upper part of the skin in which the coat of hair, wool, or 
fur is rooted, is termed the epidermis or cuticle, next beneath 
this is the corium or true-skin, and placed next to this is the 
under-skin. 

The epidermis is composed of two layers: — 

i. A tissue analogous to the corneous matter of the hoofs, 
horns, nails, and hair, and is composed of layers of nucleated 
epithelium cells, which when first formed are spherical, gradu- 
ally becoming dry and flattened ; the deeper layers being more 
distinctly cellular, while the outer layer is scale-like, and, 

2. An inferior or basis-layer, Malpighi's net {rete Malpi- 
ghianum), which consists of a layer of cells charged with fluid, 
and serves to feed or renew the horny tissue, being in its turn 
supplemented by vessels situated in the corium. 

The epidermis does not combine with tannin or other sub- 
stances by the agency of which leather is produced. Hence it 

(21) 



22 THE MANUFACTURE OF LEATHER. 

becomes useless to the tanner, and therefore the first process 
to which hides and skins are subjected by him is that for re- 
moving the hair and epidermis, and the portion of the skin 
thereby exposed is technically termed the " grain side." 

The corium or true skin is divided into an intermediate layer 
next to the epidermis, and is the actual leather-skin. 

Both are made up of interlaced bundles of connective tissue 
fibres, placed crosswise above each other, and running parallel 
with the surface of the skin ; but being more or less filled with 
fluid matter that serves to renew the cuticle and maintain the 
skin in a pliant and moist condition. On treating the skin with 
water these matters are removed, and ultimately there remains 
but the fibrous portion saturated with water. In this state it 
appears semi-transparent, and if the water be expelled by a 
gentle heat, it assumes the physical appearance of horn, con- 
stituting only about 32^ to 33 per cent, of the raw hide. 

The quality of the leather which can be produced from a skin 
depends upon the thickness, flexibility and strength of the 
corium, which exceeds the combined thickness of all the other 
layers forming the remainder of the skin. 

A peculiar albuminoid substance (cori'in) is stored between 
the separate fibres of the corium, which substance in a dry 
state connects and cements together the raw skin fibres. 

The under-skin consists of a loose connective tissue, in which 
the sweat and fat glands, the blood-vessels and muscular fibres 
are embedded. It is previously removed in the " beam house " 
of the tannery, and takes no part in the tanning process. 

The side upon which the connective tissue of the under skin 
is located is technically designated as the " flesh side.-" 

Fig. 3 shows an enlarged transverse section of the skin. 

D is the connective tissue of the under-skin showing the 
sweat glands g, with the ducts h, through which this secretion 
passes out to the surface of the skin ; b is the Malpigki net, and 
d the corium ; c, papillae of the skin ; e, f, lobules of adipose 
tissue ; i, the external orifices of the sweat or perspiratory 
glands ; k, hair follicle ; ,m, hair papilla ; n, hair bulb ; 0, shaft 
of hair in hair follicle ; p, openings of the sebaceous glands. 



ANIMAL SKIN. 



23 



The horny layer of the epidermis, a, shows on different 
places, as at /, such structures as hair, wool, bristles, etc., 
which, as seen in the illustration, are not embedded immediately 
in the surface, but in capsules or shafts, called "hair sacs" or 
"hair roots," reaching from the epidermis to the actual corium. 
In these sac-like depressions the hair is fastened by means of 
"hair bulbs." The hair is coated with a protective layer of fat 
by small fat glands, the follicles of which enter the upper part 
of the hair-sac. 



Fig. 3. 










Malpighi's rete mucosum accompanies the bottom of the 
hair sac, the walls of the latter consisting of flat epithelial cells, 
which develop, only in another form, the hair itself. 

The horny shaft of the hair is a section projecting above the 
skin, and when completely developed is provided with a minute 
epithelium, forming the upper skin of the hair. 

In boiling with water the connective tissue fibres are con- 
verted into glue, the other constituents taking no part in the 



24 THE MANUFACTURE OF LEATHER. 

glue formation. The chemical process taking place during the 
latter operation is not yet thoroughly understood. The rela- 
tions of the glue-yielding tissues to the glue, seem to be similar 
to those existing between starch and paste. Starch, as well as 
the glue-yielding tissues, is a body of an equally pronounced 
nature, both being insoluble in cold water and remaining unal- 
tered within certain limits. By boiling with water, they en- 
tirely lose their organized structure and form a solution, which 
on cooling separates, in glue, a colorless jelly, and in starch a 
body very similar to glue. 

The skin, when slowly and completely dried in the air and 
stored in a dry place, can be kept for a long time. When dried 
by exposure to strong sun heat, it undergoes an alteration 
having an injurious effect. The fibres of such skin, after com- 
plete softening by soaking, which can only be accomplished 
with great difficulty, show very little strength. This excessive 
effect of heat may even cause the skin fibres to dissolve, in 
soaking, into a glue-like jelly, as has, for instance, been fre- 
quently observed in buffalo skins carelessly dried by exposure 
to strong sun heat. 

Moist skins left to themselves decompose in a short time with 
the usual products of putrefaction making their appearance. 

Covered with salt or immersed in strong brine, skins can be 
kept for a long time. By adding borax to the brine the quan- 
tity of salt used can be greatly reduced, one pound of borax 
doing the work of five pounds of salt, and it at the same time 
preserves the s^ffin much better condition than when salt 
alone is used. 

The chemical and morphological constitution, as far as inter- 
esting to us, may be briefly given as follows : — 

"The connective tissue fibres or fibrillae form the morpho- 
logical structure of the skin tissue, the intercellular substance 
or coriin, as has been conclusively shown by Rollet,* and later 
by Reimer,f lying between them. 

* Wiener Akademieberichte, 30, 37, 39, 308; and Dingl. Polyt. Journal, 149, 298. 
f Dingier, Polyt. Journal, 143, 205. 



ANIMAL SKIN. 2$ 

The intercellular substance is an albuminous body, according 
to Roller, and Reimer, soluble in lime and baryta-water, and 
also, according to Reimer, in a 10 per cent, solution of common 
salt, while in one of greater or less concentration it remains in- 
soluble. This behavior towards solutions of common salt and 
lime-water can therefore be used for separating it. 

To prepare corhn the skin is washed with water until all the 
soluble albuminoid substances are extracted. The skin is then 
placed in saturated lime-water six to eight days, which dissolves 
all the cori'in. The fluid is then filtered, and dilute acetic or 
hydrochloric acid added until the appearance of a slight acid 
reaction. The cori'in is separated as a flaky precipitate which, 
by standing quietly, settles on the bottom. 

To obtain the coriin perfectly pure and free from an admix- 
ture of cell elements, it is redissolved in lime-water, filtered, and 
again precipitated with acids. Coriin precipitated from alka- 
line or common salt solution is constant in all respects ; on de- 
taching it from the filter gray or gray-white lamina are formed, 
which on exposure to the air assume a somewhat darker color. 
On shaking up with water, it swells up without actually dis- 
solving, and is converted into a paste-like mass. By diluting 
the latter with water an opalizing fluid is obtained, which by 
standing forms a precipitate, nothing whatever remaining in 
solution. The addition of a small quantity of common salt in- 
creases the swelling capacity, while that of a larger quantity 
promotes solution, and that of a saturated solution of common 
salt effects precipitation. By adding spirit of wine to the sub- 
stance dissolved or swelled in water, a flaky precipitate is 
separated. 

After removing the spirit of wine the flakes act in the same 
manner as before. Precipitation may also be effected by ether, 
but as the precipitate for some time remains in contact with 
the ether, it can be swelled only with difficulty. Most of the 
alkaline salts and alkaline earths have, like common salt, a dis- 
solving and swelling effect upon corhn, small quantities of them 
increasing its solubility in water, which is a very important fact 
deserving special attention in tanning. 



26 THE MANUFACTURE OF LEATHER. 

Most natural waters, as is well known, contain small quanti- 
ties of alkaline salts and earths. In using such water for swell- 
ing, cleansing and washing the hides, the swelling influence 
which these salts have upon the coriin must be taken into 
consideration. 

In hard water containing much of these salts, the skins must 
remain for a shorter time than in soft water, i. <?., such as con- 
tains but a small quantity of salts, or none whatever. 

In speaking of the use of water in the tannery, we have con- 
sidered this point more closely, and the reader is referred to 
Chapter I. 

Since by repeated treating with lime or baryta water, fresh 
quantities of soluble substances can be constantly withdrawn 
from the skin, it is not improbable that the intercellular sub- 
stance is a product of decomposition of the connective tissue 
substance. This circumstance deserves consideration in depil- 
ating the skins and hides with lime, for if the latter remain too 
long in the lime, a part of the connective tissue is converted into 
soluble substance, which is lost in the succeeding cleansing of 
the hides. 

Liming continued too long gives poor weight, and besides 
the strength of leather prepared from skins too long limed is 
impaired. 

Coriin is insoluble in acetic acid, and only partly soluble in 
dilute hydrochloric acid, the undissolved portion settling after 
long standing, as a flaky precipitate. 

Coriin is readily soluble in pure alkalies and solutions of 
alkaline earths. 

Potassium ferrocyanide and ferricyanide produce no precipi- 
tation in acidulated or neutral solution, but effect precipitation 
when acting upon strongly swelled coriin. 

Ferric chloride, cupric sulphate, cupric chloride, and sugar 
of lead form no precipitate in neutral or slightly alkaline solu- 
tions, while it is produced by basic acetate of lead, excess of 
tannic acid or basic acetate of iron. 

Coriin is free from sulphur, since on melting the substance 



ANIMAL SKIN. 27 

with potassium hydrate no potassium sulphide remains behind. 

From the composition found by the elementary analysis, 
Reimer derives the empirical formula C 30 H 50 N 10 O 15 . 

The connective tissue substance* differs in many respects 
from the intercellular substance, but principally by being in- 
soluble in lime-water, which, as we have seen, readily dissolves 
coriin. It is dissolved by acetic, hydrochloric and other acids, 
but separates again on neutralization. 

To prepare connective-tissue substance, place cleansed skin 
in acetic acid for some time. The skin swells up more and 
more, while the acetic acid dissolves a portion of the connective- 
tissue substance. The fluid becomes of a slimy nature and 
separates on being diluted with water, filtered and neutralized, 
to a flaky precipitate. To obtain the substance in a pure state, 
this precipitate is washed with lime-water in order to remove 
coriin which may be present, and is again dissolved in acetic 
acid. Some potassium is added to the solution until only a 
very slight acid reaction is perceptible. The fluid is then 
saturated with common salt, the precipitate, after standing 
quietly, collecting upon the surface. It is filtered, and first 
washed with slightly acidulated water, and then with pure 
water, and finally dehydrated with alcohol. 

Pure connective-tissue substance swells up when placed in 
water, and reassumes its original softness. 

Acetic acid, as previously mentioned, dissolves connective- 
tissue substance, the solution containing the substance but it is 
not dissolved as glue. Potassium ferrocyanide and ferri- 
cyanide produce precipitates in the solution. 

By boiling with water, the pure substance is readily con- 
verted into glue. 

Pure lime water does not dissolve it; an essential difference 
from coriin. 

Tannic acid, basic acetate of lead, and basic sulphate of iron 
produce precipitates. 

* Muspratt, Technische Chemie, Bd. III. 91. 



28 THE MANUFACTURE OF LEATHER. 

The empirical formula C 15 H 23 N 5 6 is derived from the ele- 
mentary analysis. 

This being the same composition as that found by Cramer 
for the fibroin of silk, Reimer designates the matter extracted 
by acids from the skin as skin fibroin. 

The empirical formulae calculated for cori'in and skin fibroin 
give us no information as to the relation or close analogy of 
the two bodies to each other, their chemical constitution being 
still unknown. 

The most important property of the skin fibre, which de- 
serves special attention from a practical standpoint, is that it 
swells up strongly in one-half per cent, solutions of inorganic 
acids, and is entirely dissolved in somewhat concentrated acids 
if subjected sufficiently long to their action. 

The swelling influence exerted by acids upon the skin fibres 
is, as is well known, used on the one hand to make the skin 
more sensitive for the reception of the tanning material, and, on 
the other, to effect the isolation of the compound bundles of 
connective-tissue fibres into separate fibres, increasing the 
surface thereby at the same time. It is self-evident that by 
carrying this swelling process too far, the strength of the fibre 
suffers injury. 

For swelling the skin acetic and lactic acids are chiefly used ; 
of these the latter is more effective than the former. 



CHAPTER III. 

VEGETABLE TANNING MATERIALS. 

BUT few of the large number of vegetables containing tannic 
acid are used in tanning, though in modern times the number 
has been greatly increased by diligent researches made with a 
view to obtain cheaper tanning materials. 

We shall here discuss the most important of such materials, 
first mentioning the inspissated vegetable juices which are 
imported. 

Rutea is the inspissated juice of Rutea formosa, and is used 
for tanning only in the northwest of India. 

Kino is the inspissated juice of Pterocarpus erinaceus and 
marsupium. Numerous varieties of kino are known in com- 
merce, though the principal ones are those coming from Africa 
and Malabar. The African kino, which is the best, but seldom 
found in commerce, is the inspissated juice of Pterocarpus 
erinaceus. 

The Malabar, or East Indian kino, is derived from Pterocar- 
pus marsupium, a tree indigenous to Farther India, Malabar 
and Ceylon. Both varieties of kino are very rich in tannic acid, 
that of the latter being identical with gallotannic acid, it yield- 
ing, on heating, pyrogallic acid. On account of its high price, 
and the disagreeable red color it imparts to the leather, this 
tanning material is but little used. 

» Gambler is an extract from the leaves of Uncaria gamblr. 
It forms cubical pieces -^ to -§- inch thick of a light and dark 
rust color or sometimes gray color, which float upon water and 
are very friable. Gambier is slightly soluble in cold water, but 
readily in hot. Its percentage of tannin is quite high. 

Catechu, or terra japonlca, is the dry extract from the heart 

(29) 



30 THE MANUFACTURE OF LEATHER. 

wood of a mimosa, Acacia catechu, growing in the East Indian 
islands. Its principal constituents are: Catechin, a brown sub- 
stance which can be precipitated from its solution with glue, 
and catechutannic acid, which appears to be formed from the 
catechin by exposure to the air. It colors ferric oxide green, 
and gives a green-black precipitate with ferric salts. The 
value of catechu may be judged by its external color, hard- 
ness, taste, solubility in spirit of wine, etc. Genuine catechu 
melts upon the tongue, while non-genuine sticks to it. Adul- 
terations with blood, sugar, etc., can be detected by the 
characteristic odor of these admixtures when burnt. The 
leather produced with catechu is not of a particularly good 
quality, it being of a dark color, permeable to water, spongy, 
and at the same time hard. 

Gall-nuts are the richest in tannin of all tanning materials. 
They are morbid excrescences of the leaves and young 
branches of Quercus infectoria, Oliv., formed by the puncture 
of gall-flies {Cynips gallce tinctorial), belonging to the Hymen- 
optera, for the purpose of depositing their eggs. As the latter 
develop, excrescences called galls or gall-nuts are formed on 
the punctured places by the exudation of sap and enlargement 
of the cells. The larvae which are inclosed in the galls are sup- 
ported by the juices of the plant until they become perfect 
insects, when they perforate the gall and escape. When this 
happens the excrescence loses much of its astringent prfnciple 
and becomes lighter in color and finally entirely white, while if 
collected before the entombed insect is completely developed, 
the galls are of a dark to blackish color, and much richer in 
tannin. 

The latter are known in commerce as green galls, and come 
from Aleppo, Smyrna and Mesopotamia. 

Gall-nuts are also imported from Cypria, Karamania, etc., 
though they are not so good as the Aleppo galls, with which 
they are sometimes mixed. 

European galls, formed by the puncture of other species of 
gall-flies on other varieties of oaks, are not so good as the 



VEGETABLE TANNING MATERAILS. 3 I 

Aleppo galls. They come from the Morea, Italy, Hungary and 
Istria. Gallotannic acid is, as previously mentioned, the most 
accurately known. 

Galls (Knoppern) formed by the puncture of a gall-fly 
( Cynips quercus calycis) in the young fruits of Quercus pedun- 
culata. They are principally collected in Hungary, Dalmatia 
and Slavonia, and contain, besides a small quantity of gallic 
acid, much tannin closely resembling gallotannic acid. The 
percentage of tannin amounts, according to Mueller, to as much 
as 50 per cent. 

Chinese Gall-nuts form irregular roundish bulbs of the size of 
a hazel or walnut, which inclose the insect. Their rind is 
smooth and felt-like, of a gray or reddish color, and very thin, 
and consequently fragile. They show no vegetable structure, 
but a dense, brilliant, resinous fracture, and are said to be de- 
rived from a species of sumach. They are much in demand on 
account of their high percentage of tannin, which, according to 
Mueller, amounts to as high as 65.5 per cent. 

Rove. — The. article known by this name, which is brought 
into commerce ground and pressed in bricks, is the so-called 
Bassora gall-nut, and is found in Persia and Asia Minor. It is 
principally exported by way of Smyrna. It contains about 27 
per cent, of tannic acid. Mixed with oak or fir bark, it is, 
according to Eitner, well adapted for tanning sole leather. 

Sumach consists of comminuted leaves, stems of blossoms, 
and branches of several Rhus species, such as Rhus coriaria, R. 
cotinus, R. glabrum, R. canadense, R. typhinum, R. pentaphyllum, 
Arbutus uva ursi, Cyriaria myrtifolia. 

The following varieties are found in commerce : 

Sicilian Sumach, from Rhus coriaria, is the most valued. It is 
divided into two qualities, the best being of a greenish-yellow 
color, while the inferior variety is of a more rusty-yellowish 
color, and has less smell and less tannic acid. 

Italian Sumach, which is also derived from Rhus coriaria, is 
a dirty-green powder. It is far inferior in tanning capacity to 
the Sicilian variety, it being besides frequently adulterated with 
sondro leaves. 



32 THE MANUFACTURE OF LEATHER. 

Spanish Sumach. — Three varieties of this occur in commerce, 
viz : Malaya or Priego, Malino, and Valladolid, the last two 
being of less value than the first. 

Tyrol Sumach, the odor of which resembles that of oak bark, 
is derived from the leaves and stems of Rhus cotinus. Like 
the Italian and Sicilian sumach, it is frequently adulterated with 
fig leaves. 

French Sumach (irom Coriaria myrtifolid). 

There are four varieties : Fauvis, Redoul, Donsere, and Pudis 
sumach, the last two being less liked than the others. 

The " Tezera " sumach, used by the Arabs for tanning mo- 
rocco leather, is derived from Rhus pentaphy 'Hum. 

American sumach is derived from Rhus canadense and R. 
glabrum. Large quantities of it were formerly used in the United 
States, the morocco manufacturers mixing it with an equal 
quantity of Sicilian sumach to form the tanning liquor, which 
was forced through the goat skins by hydrostatic pressure. 
Sumach is also used in tanning patent, enameled, and furniture 
leathers, sheepskins and grain, split and buffed leathers. 

Swedish Sumach is prepared from the leaves of the bear-berry 
(Arbutus uva-ursi). 

It is not yet definitely determined whether all the different 
varieties of sumach contain the same or different kinds of tan- 
nic acid, although the latter is most probable. 

The tannic acid contained in the Sicilian sumach is, accord- 
ing to Stenhouse,* identical with gallotannic acid. In old sum- 
ach, the larger portion of the tannic acid has been converted 
into gallic acid and sugar. 

Leather prepared with sumach possesses but little capacity for 
resisting water, and is therefore principally used for book-bind- 
ing, portfolios, pocket-books, linings, bindings, skivers, etc. 

Chrome tannage has however driven sumac almost entirely 
out of the morocco trade. 

Valonia is the acorn-cup of Quercus cegilops, the prickly- 
cupped oak, a tree growing in abundance in the islands of the 

*Dingl. Polyt. Journ. clxv. 150. 



VEGETABLE TANNING MATERIALS. 33 

Grecian Archipelago. The tannic acid of valonia is not known 
in a pure state, as it always contains gallic acid. The use of 
valonia has recently much increased in Europe, it being espe- 
cially employed, mixed with oak tan, for sole-leather in the 
last two spreadings of the hides in the binders. Leather pre- 
pared with valonia, is said to be harder and less permeable to 
water than that made with oak bark, its weight being also 
increased. The price of valonia which contains a considerable 
percentage of tannic acid, is low compared with that of tan, 
and it is much used by English tanners. 

Divi-divi consists of the dried pods of a bush (Ccesalpinia 
coriaria) indigenous to South America. Leather tanned with 
the extract becomes very soft and spongy, and on exposure to 
the air assumes a more or less brown to brown-red color. The 
extract of the divi-divi pods is also brought into commerce. 
The tannic, acid differs from the gallotanic acid, and, when 
heated, does not yield, like the latter, pyrogallic acid. 

Myrobalans, the dried fruit of Terminalia chebula, is princi- 
pally collected in India. The fruits exported by way of Calcutta 
are of a roundish shape, gray-black color, and hard and astrin- 
gent. They contain, principally in the husk, a considerable quan- 
tity of gallic acid, which, according to Stenhouse, differs so far 
from gallotanic acid as not to yield, on boiling with dilute sul- 
phuric acid, gallic acid, but a reddish-brown substance insoluble 
in spirit of wine. 

Myrobalans are used in Europe in tanning as an addition to 
oak bark. 

Bublah is the husk of the fruit of Acacia bambula. It comes 
from India, and contains considerable tannic acid. 

Of the other foreign materials containing tannic acid, which, 
on account of their high price, etc., are more extensively used 
in dyeing and coloring than tanning, we will mention : — 

Logwood, which is derived from H&matoxylon campeachianum, 
a Casalpina growing wild in Yucatan and some of the West 
Indies. 

Fustic, obtained from Morns tinctoria. It contains a peculiar 
3 



34 THE MANUFACTURE OF LEATHER. 

tannic acid, moritannic acid, or macherin, which on heating 
yields pyrocatechin. It is only used for coloring leather. 

Weld (Reseda luteola) is a plant belonging to the Resedacecs, 
which grows wild in all European countries, though it is occa- 
sionally cultivated in Southern France and in Germany. 

The following barks are also made use of in tanning, although 
not so extensively as hemlock and oak barks: — 

Larch bark (Larix Europcza). — This bark yields a material 
relatively poor in tannin. It contains, according to Davy, 1.6 
to 2 per cent, of tannic acid. The bark is used in England and 
Ireland for tanning sheep-skins. 

Fir bark (Pinus abies) is principally used in Europe, in Aus- 
trian, Bavarian, Hanoverian, and Upper Swabian tanneries. It 
is claimed to be especially adapted for "plumping," or the so- 
called preparatory swelling and tanning of hides. 

Hemlock bark is obtained from Abies Canadensis. 

The bark is light, has a somewhat balsamic odor, and a 
slightly astringent taste. The tannin is colored green by ferric 
salts, and brown by potash lye. It is the most important tan- 
ning material of America, where it is much used for tanning 
both sole and upper leathers, two-thirds of all sole and upper 
leathers produced in the United States being tanned with it. 
This variety of leather has only lately been appreciated in many 
portions of Europe, and our exports of it are constantly in- 
creasing. A mixture of hemlock bark and oak, termed " union 
tannage," gives a very serviceable leather. 

An extract of hemlock bark goes into the European markets 
under the name of American hemlock extract, and it is also em- 
ployed in portions of this country where bark is scarce. 

It is chiefly prepared from thick bark, since the greatest yield 
of tannin is, according to Eitner, obtained from the rind, and not 
from the pulp, an analysis of the latter showing 7.7 per cent, of 
tannic acid, and of the former 11.3 per cent., while the entire 
bark yielded 10. 1 per cent. 

Oak bark, from Qnercns monticola of Michaux, rock chestnut 
oak, and Q. tinctoria, the yellow-barked oak, are the most highly 



VEGETABLE TANNING MATERIALS. 35 

esteemed for tanning purposes in the United States. The best 
is the first-named variety, and the prime quality is derived from 
the Blue Ridge, which is the most easterly ridge of the Allegheny 
Mountains. The principal tanneries using rock chestnut-oak 
bark are located in the state of Virginia, the western portions of 
the Carolinas, and in Tennessee ; the bark in the latter state being 
derived from the Cumberland Mountains. In tanning it is used 
unmixed, and gives a beautiful "bloom;" the sole leather pro- 
duced with it being always in demand for both home consump- 
tion and for export. The oak tan bark of Mendocino county, 
California and of the upper coast of that state is probably the 
finest in the world for tanning purposes. The bark of the yellow- 
barked oak is in tanning commonly mixed with red-oak bark, 
as the color which the former yields when used alone is objec- 
tionable. 

The inner bark of the Q. tinctoria is the quercitron of dyers. 
The barks of the Q. alba, white oak, and Q. rubra, red oak, are 
not esteemed in tanning, the first being poor in tannin and the 
second imparting an undesirable color to the leather. 

Canaigre. — In the rainless regions of the southwest, the Az- 
tecs, Zunis, Pueblos, and later on the Mexicans, have for cen- 
turies been tanning hides with, the root of a sour dock or wild 
rhubarb, Rumex kymenosepalus, called by the early missionaries 
sour cane, " Cana agria," which was finally pronounced cah-na- 
ger, and spelled canaigre. 

The commercial value of canaigre depends upon its tannic 
acid. This is found in all parts of the plant, its leaves, seeds 
and flower stalks, but mainly in its roots, of which it; iorms an 
average of about nine per cent, in the green state. Of import- 
ance also in tanning are certain red and yellow coloring mat- 
ters which are extracted along with the tannic acid, and which 
affect the quality of canaigre-tanned leather. As much as three 
per cent, of starch is also found. This is an undesirable con- 
stituent, causing trouble in the tanneries unless it is removed by 
a suitable process of extraction. The roots contain an average 
of about yo per cent, of water, more or less, according to the 
age of the plant and the abundance of water supply. 



36 THE MANUFACTURE OF LEATHER. 

The amount of tannic acid varies much with conditions of 
growth. Adverse environment seems to be associated with the 
largest percentage, while well-irrigated roots, grown in rich soil, 
show a distinct decrease. The lighter color of cultivated roots, 
however, is said to be preferred by tanners. During the annual 
period of growth the tannins seem to increase most rapidly at 
the beginning of summer, when the plant is dying back to the 
ground. It appears that at this time the astringent sap of the 
leaves retreats into the roots, contributing materially to their 
percentage of tannic acid. 

Professor Forbes says : 

" As regards the value of canaigre tanning materials, the 
earlier favorable opinions of tanning chemists have been excel- 
lently supported by the experience of the trade. From various 
sources it is learned that canaigre chips and extracts have been 
successfully employed either alone or in connection with other 
tanning materials for the production of a remarkable variety of 
leathers, including both heavier and lighter grades. According 
to the statement of different tanners, it is employed in the pro- 
duction of: 

"I. Patent and enameled leather for the carriage, saddlery 
and upholstery trades. 

"2. Patent and enameled leather for fine shoes. 

"3. Carriage covers and dashboard leather. 

"4. High grade of carriage and furniture leather and a fair 
grade of patent shoe tipping. 

"5. Upper, grain, or similar light leather. 

" 6. East India kips finished as waxed leather. 

" 7. Yellow for mittens, horse hides, butts, kangaroo, glazed 
kid, and other fine shoe leather. 

" 8. The heaviest sole and harness leather, and the lightest 
calf and sheep, with best results for all kinds." 

Quebracho is a Spanish word meaning axe-breaker, from the 
toughness of the tree, which breaks the sharpest axes. It is a 
tree which grows only in Gran Chaco in the Argentine Republic. 
Two species are known, the Quebracho bianco, which is only 



VEGETABLE TANNING MATERIALS. 37 

used for building purposes, and Quebracho Colorado, or red wood. 
It varies in color from gray to dark, which depends entirely 
upon the tanning and coloring matter which it contains. 

The material is too strong in tannin, possessing insufficient 
non-tanning proprieties to yield well-nourished leather unless 
combined with agents which are stnonger in non-tanning sub- 
stances. 

The discovery of the valuable tanning properties of this wood 
is due to Mr. George Fahr of Pirmasens in Bavaria, who on a 
visit to the Paris Exposition of 1867 saw quebracho wood from 
Gran Chaco exhibited as a dye-wood. He had it analyzed in 
Vienna and found that it contained 22 per cent, of tannin and 8 
per cent, of coloring matter. This led him to import some of 
the wood. Later analyses were equally favorable, and in 1871 
several firms in Havre and Antwerp imported considerable quan- 
tities of the wood. Mr. Fahr and his brothers then got up machin- 
ery to rasp the wood, and by 1876 were enabled to furnish con- 
siderable quantities of quebracho chips to Alsatian, Rhenish and 
Swiss tanners. But through the improved tannage obtained by 
using quebracho wood Messrs. Fahr found their leather in such 
demand that they were compelled to give up the supplying of 
quebracho wood to other tanners, as they used all they could 
produce in their own tannery. Tanneries in Argentina also kept 
pace in tanning with quebracho, and the primitive tanneries of 
that country soon grew into enormous establishments. As their 
hides and tanning material were at hand and cheap, they quickly 
obtained European markets for their leather, which markets 
were needed to prevent overproduction in a country that only 
offered poor markets for them. The leather made with que- 
bracho is superior both in firmness and color. 

The quebracho tree of Gran Chaco is about 18 to 36 feet in 
height and has a diameter of 18 to 40 inches. When first felled 
the color is a light yellow but on exposure it turns to a light red. 

The best wood comes from Vera, three days journey from 
Buenos Ayres on the railroad leading from Santa Fe to Garabato, 
where virgin forests are found along the Parana and the Picole- 



38 THE MANUFACTURE OF LEATHER. 

majo rivers. It is said that when quebracho wood is of good 
quality and freshly rasped it retains much natural moisture so 
that it will ball up in the hand. This moisture is said to be due 
to the quantity of tannin it contains, and which when first felled 
oozes from the cut surface like resin. 

At a convention of German tanners held in Hamburg, Pro- 
fessor Eitner in his speech made some interesting remarks on 
the uses of quebracho. 

The speaker said that the advantages of the quebracho wood 
consisted not only in making the tanning cheaper on account of 
the low price of the material and the obtaining of a larger out- 
put, but also on account of effecting rapidly a thorough tanning 
especially for certain kinds of leather ; and a splendid product 
can be obtained by the addition of quebracho wood to the liquor. 

"All tanning matter," said the speaker, "contains, if I may 
so express myself, three different kinds of tanning material, to 
wit., one pale and readily soluble, which penetrates the hide very 
easily and impregnates the fibre itself ; a darker one a little less 
soluble, which also enters the hide easily and is fixed to the ex- 
terior part of the fibre ; and one almost insoluble, which only en- 
ters the hide by violent means and which makes the leather dark 
colored and of a disagreeable appearance. 

"Now, it is in the wood of quebracho that the first of these 
tanning substances is found in large quantities, and explains the 
fact that the pale liquor of quebracho wood penetrates so easily 
into the hide, more readily even than sumach. And it is this 
quality that renders quebracho particularly valuable to the 
tanner. 

" If the quebracho is not qualified to furnish a solid leather 
in the ordinary process of tanning — if the leather tanned with 
this substance fails in some qualities — it is on the contrary par- 
ticularly adapted to tan the hide promptly and thoroughly, and 
to render it proper for the absorption of strong liquor, that is to 
say, the thickest." 

To obtain a solid and completely saturated leather the 
speaker recommends a mixture of quebracho and oak bark as 



VEGETABLE TANNING MATERIALS. 39 

being practically efficient. " Oak bark," said he, in substance, 
" is not the enemy of quebracho wood ; as the two tanning sub- 
stances can be used together. By adding to the oak bark some 
quebracho wood the expense of the tanning is decreased and 
leather is obtained which in quality and appearance is the equal 
of that tanned with pure oak liquor. Good results may also be 
had by mixing other kinds of tannin with the quebracho, which 
is of benefit to the small tanner." 

A sample of leather tanned with quebracho extract will be 
found with the other samples at the end of this book. It is 
furnished by A. Klipstein & Co., who are the pioneers in que- 
bracho in this country and the chief importers, handling as they 
do the output of the principal factories of the world furnished 
for American consumption. 

Quebracho is especially interesting because of its adding 
weight and firmness to leather, and also because it furnishes 
light leather, which is excellently well adapted for the taking 
of all sorts of dyes ; and heavy leathers of all kinds of excel- 
lent quality. 

A. Klipstein & Co.'s head office is in New York, and their 
branch offices are in Philadelphia, Boston, Chicago, Providence, 
Cincinnati, and Hamilton, Ont., where stock is carried and full 
information furnished as desired. 

A. Klipstein & Co. have issued a little pamphlet descriptive 
of the qualities and use of quebracho. It is interesting as 
showing the extent of the sale of this tanning material and its 
utility for the purpose intended. They give the analysis of the 
quebracho from a tract of land at Gran Chaco, as follows : 

Tannic acid 28.20 

Foreign substances 1.70 

Extract ashes 0.40 

Water... 11.85 

Insoluble parts 57-85 

100.00 
For some years past quebracho has been employed in every 



40 THE MANUFACTURE OF LEATHER. 

European tannery with success, and the following figures will 
show that within the last four years the exports from the Ar- 
gentine Republic to Europe have rapidly increased, as follows : 

1 892 29,700 tons. 

x 893 49>4°° " 

l8 94 54,54° " 

1895.. 154,000 " 

Of all European countries, Germany has become the largest 
consumer, having used it chiefly for sole leather. The result 
has been the almost total destruction of the American export 
trade in sole leather to Germany, as may be seen from the 
U. S. Treasury reports as follows : 

Sole Leather Exported to Germany from the United States from 
1876 to 1896. 
Pounds. Pounds. 



876 6,400,000 

877 6,100,000 

878 7,100,000 

879 7,500,000 

880 3,900,000 

881 3,600,000 

882 2,500,000 

883 2,400,000 

884 2,500,000 

885 3,000,000 

886 2,000,000 



887 1,900,000 

888 1 ,800,000 

889 i,6oo,oco 

890 1,700,000 

891 1,400,000 

892 816,000 

893 548,000 

894 542,000 

895 733,ooo 

896* 186,000 



* For 10 months. 

The quebracho tree grows in the large forests known as Gran 
Chaco, situated in the northern part of the Argentine Republic. 
The logs, which are employed for tanning purposes only, are 
used without the bark and run from 5 to 10 meters in length 
with a diameter of from 50 to 100 centimeters. The best wood 
grows north of Vera Station on the railway line from Santa Fe 
to the Gran Chaco (Garabato). These forests extend in the 
north as far as the river Bermejo, and in the east as far as the 
river Parana. 

There are also some small forests situated on the opposite 



VEGETABLE TANNING MATERIALS. 4 1 

shore of the river Parana, in the Province of Corrientes, and 
some in the west as far as the Provinces of Salta and Santiago 
del Estero. 

The soil of the surrounding provinces is unfit for the growth 
of quebracho, and the trees found in the districts of Corrientes 
(Empedrado) and Satiago del Estero, are small and poor, which 
accounts for the bad quality of the quebracho coming from these 
provinces, while the Gran Chaco product, on the contrary shows 
far stronger tanning proprieties combined with a lighter color. 
Tanners will understand the importance of always using the 
better quality of quebracho when they know that the inferior and 
cheaper kind, besides containing far less tannic acid, is also full 
of a peculiar dye-stuff which gives the leather a dirty color and 
decreases- its weight, while pure Gran Chaco wood gives the 
leather a clear light yellow tint, and considerably increases its 
weight. 

The advantage in the use of quebracho lies in the fact that the 
tanning process is rendered much cheaper, owing to the low 
price of the tanning material and the better results obtained. 
Besides, the process is more rapid and the tanner is enabled to 
obtain by it good leather of various kinds. 

The best results are obtained by mixing quebracho with other 
tanning materials, and the German tanners have successfully 
employed a mixture of quebracho and oak or fir bark. 

Different tanning materials, such as hemlock, gambier, can- 
aigre, oak or fir mixed with quebracho, give the very best re- 
sults, and the use of quebracho considerably reduces the expense 
of tanning sole and upper leather. 

Those who have carefully tested quebracho are now steady 
consumers of it, and are fully satisfied as to its good properties. 

The following process is given for using pure quebracho 
wood for sole leather in Buenos Ayres, taking as an illustration 
30 cow hides : 

First or coloring liquor. — The hides are first treated with 
some partially exhausted liquor 4 to 6 degrees in strength. If 
there is no such liquor employ clear water with quebracho of 



• -~ 



42 THE MANUFACTURE OF LEATHER. 

the strength above mentioned, then handle about four times 
until an even color is obtained. Much attention should be 
given to the first liquor so that the leather receive a light color. 
Should the liquor be cloudy use a little alum-water to clear. 

Second Liquor. — For 30 cow hides put 180 kilos, quebracho 
chips in vat with fresh water and handle the hides several times 
for a couple of days. Take out the used wood and put in some 
180 kilos, more, then handle twice a day until all the tannin is 
extracted from the wood, probably in about four days. 

Third Liquor. — Put 200 kilos, quebracho in vat with fresh 
water, handle the hides in this once a day for six to eight days, 
when they will be ready for laying away. 

At the laying away hides receive about 26 kilos, quebracho 
per hide on the grain side. When the vat is filled add the liquor 
from the spent wood out of former steeping and let the hides 
rest 25 to 30 days. After this take the leather out of the vat, 
rinse it well in previously used liquor, and let it run dry without 
liquor or water in the^fashwheel. 

About half an hour will suffice to make the leather pliable. 
To work it on the table give it a good washing with water and 
sulphuric acid, then dry and roll the leather carefully. 

Hides worked in this way show a bright clear yellow color 
and good weight, and are quickly tanned. 

Method for employing quebracho with oak bark for sole leather 
in Europe, as recommended by Mr. Eitner at the Tanners' Con- 
vention in Hamburg: — 

In the manufacture of heavy sole leather, which presents the 
greatest resistance to the absorption of the liquor, the following 
method is recommended for an ordinary pack : 

During the swelling it is not only important that the acid of 
the liquor should preponderate, but also that it should be pure 
and free from all injurious fermenting substances. The hides 
should be left in soak 24 to 28 hours — then rinsed and replaced 
so as to be in proper condition for the liquor. While in the first 
and second liquor they are treated to a mixture of Jyi kilos, 
of quebracho and an equal quantity of oak bark ; if a third 



VEGETABLE TANNING MATERIALS. 43 

liquor is necessary use a mixture of 60 parts of quebracho to 
40 parts of oak bark, and leave them in the liquor for about 
20 days. By this repeated and prolonged immersion the time 
employed for tanning is considerably shortened. 

At the first laying away the hides will receive 20 kilos, of 
powdered matter, consisting of 60 parts quebracho to 40 of 
oak bark; on the second laying away a larger proportion of 
quebracho may be employed. Time of immersion about the 
same — about 20 days. 

The washing is done with the spent liquor obtained from the 
previous operations. 

The feature in the sole leather situation in the United States 
since the bank-panic of 1893 has been the growing call for 
cheap stock, this being true not only in regard to sole leather, 
but consumers seem to demand cheapness in nearly all kinds 
of leather. This must tend to an increase in the consumption 
of tropical tanning materials used in connection with the old 
fashioned bark liquors. The growing importation of foreign 
tanning material has had the effect of considerably cheapening 
domestic oak bark. Oak-tanned leather can be produced at 
less cost to-day than ever before. 

However, even where oak bark is used, the desired results, 
i. e., cheapness and rapidity, can only be attained with concen- 
trated liquors, and soon, no doubt, a tannery not furnished with 
an extract plant and not using extracts such as are to be had in 
the market,- to strengthen and also to cheapen the liquors, will 
be the exception. 

Whether the production of quebracho-tanned sole leather 
will continue to increase at the present rate in Germany is a 
question hard to answer. The enlargement of the tanneries 
making this class of leather now in operation, and the number 
of new yards, either completed or in course of construction, are 
meanwhile amply sufficient to supply the present demand. 

The United States has lost its export trade in sole leather to 
Germany through the introduction of quebracho-tanning in that 
country, and probably other loss of trade with other countries 
will follow from similar causes. 



44 THE MANUFACTURE OF LEATHER. 

The importance to the leather producer of keeping himself 
fully posted on what is going on around him, can hardly be 
over-estimated. It is if possible even more essential that he 
should do so, than is the necessity of giving the closest attention 
to the department of his business involving the purchase of raw 
material and sale of the finished product. 

Quebracho is cheaper than oak bark and costs but little more 
than hemlock. Quebracho, however, is claimed to lack some 
of the important non-tanning constituents of other tanning ma- 
terials which " nourish " the leather and serve to acidify the 
tan-liquors while effecting no actual change on the organic tis- 
sue of the leather. It should therefore be used only in con- 
junction with other tanning materials, richer in non-tanning 
matter. The red quebracho contains a large proportion of red 
coloring matter, easily soluble in warm water, although vigor- 
ously resisting the action of cold. Consequently, proper pre- 
cautions must be observed, or the leather will have a reddish 
tinge. Leather tanned with quebracho alone has no specially 
distinctive color. If alum and salt are added, finer results even 
are attained than with gambier. Quebracho, alum and salt pro- 
duce a handsome pale straw-colored grain, leaving the flesh-side 
almost white. Several large establishments in Germany are 
devoted to the manufacture of quebracho extract, notably two 
in the vicinity of Hamburg, and one near Frankfort. The ex- 
tract is put up in crystallized form, containing 65 to 70 per 
cent, tannin, or as a soft paste containing about 45 per cent. 

Palmetto root. — Palmetto root is found abundantly in Florida, 
and also grows in Alabama and Louisiana. There is some in 
Tennessee. It shows 10 per cent, of tannin. The root can be 
cut up like bark. The tannin produces tough grain, and strong 
durable leather. Its action is rapid. Palmetto has long been 
studied in regard to tanning. It tans rapidly, giving pleasing 
light color, toughness and pliability, and is a good filler of 
leather. 

It has attracted much attention of late years in the south, 
a tannery using this material having been in operation at 



VEGETABLE TANNING MATERIALS. 45 

Sanford, Fla., for some time. Palmetto is a comparatively new- 
material to leather manufacturers. Its merits will no doubt be 
fairly tested particularly when offered for sale in the convenient 
form of extract. 

Chestnut oak wood is also for tanning ; it is prepared in the 
form of an extract and is fully described in Chapter V. 

Walnut bark from Juglans regia gives a very soft leather, but 
can only be otained in small quantities, 

Lombardy poplar bark gives a light-brown leather with an odor 
resembling that of Russia leather. 

Elm bark from Ulmus campestris, is especially used in Nor- 
way for manufacturing the beautiful Norwegian glove leather. 

Horse-chestnut bark, from ALsculus hippocastanum. The bark 
of this tree contains a tannin which is colored intensely green by 
ferric oxide. Besides the tannin, which is also found in other 
parts of the tree, the bark contains fraxin, fraxetin, aesculin, 
aesculetin, and aesculetin hydrate, a small quantity of a peculiarly 
yellow crystalline body and a pectine substance which is de- 
composed into formic acid, oxalic acid, and protocatechuic acid 
by boiling potash. The leaves of the horse chestnut* contain 
also tannic acid, wax, a variety of resin (C 26 H 22 O n ) and a resin- 
ous substance (C 17 H 28 7 ) possessing a peculiar odor of frankin- 
cense. The young leaves and buds contain a peculiar tannin 
to which Rochleder has applied the term li phyllocitannic acid." 

sEsculotannic Acid.^ — Different kinds of tannic acid are found 
in the horse-chestnut, aesculotannic acid (C 26 H 24 12 ) occurring, 
according to Rochleder, in the bark, leaves, flower-buds, ripe 
and unripe seeds, roots, and the trunk. In a pure state it forms 
an almost colorless amorphous powder readily soluble in water, 
spirit of wine and ether. By the action of the air and an alkali, 
or substances containing oxygen, such as chromic acid, it is de- 
composed into a brown body having the constitution C 26 H 22 13 . 
Fusing with potash changes aesculotannic acid into phloroglucin 
and proto-catechuic acid. Ferric chloride colors the tannic 
acid green. 

* Rochleder Wiener Akadem., 24 to 48; 236 to 254; 604; 607 to 657. 
f Ibid., liv. 607. 



46 THE MANUFACTURE OF LEATHER. 

An aqueous extract of the bark comes into commerce under 
the name of " horse-chestnut extract." The percentage of tannic 
acid in the extract varies according to its specific gravity. It 
is at present much used in Germany and other portions of Eu- 
rope as an addition in oak- bark tanning, and is said to give 
good leather. It is considerably cheaper than quercotannic acid. 

Willow Bark. — The following are the principal willow barks 
used in tanning ; Salix alba, S. arenaria, S.fragilis, S. purpurea, 
etc. There is not much difference in the value of the barks, 
though it is claimed that barks containing salicin, as for instance 
that of 5. purpurea, are not so good as others. The amount of 
tannin varies from 6 to 16 per cent. In Russia willow bark is 
used for tanning Russia leather, and in Sweden and Norway for 
preparing the well-known Swedish glove leather. The tannic 
acid contained in willow bark colors ferric salts green, and, when 
treated with dilute sulphuric acid, yields sugar and possibly 
gallic acid, though this is doubtful. 

Alder Bark contains a high percentage of tannin, amounting, 
according to Gassincourt, to 36 per cent. 

Beech bark from Fagus silvatica mixed with oak bark may be 
used as a substitute for the latter, but the resulting product is of 
an inferior quality. It contains according to Davy, 2 per cent, 
of tannin, and besides a peculiarly red matter and a substance 
with an odor of vanilla. 

Protacece Barks. — The trees from which this tanning material 
is obtained are indigenous to the Cape and Australia. The 
principal ones are the Protea canocarpa (knotted tree) and 
Banksia serrata. The tannin of the latter imparts a beautiful 
violet-blue color to solutions of ferric salts, while that of the 
first colors iron green. Both give a brown color with potash lye. 

Snouba Bark. — The Aleppo fir {Pinus halepensis) yields two 
important tanning matarials, namely the snouba bark, arid the 
scorza rosa. The first is the inner bark of the tree freed entirely 
from the rind, and comes from Tunis and Algiers. 

The scorza rosa is the rind of the same tree, obtained in 
Southern Italy, and especially in Sicily, from the living trees in 



VEGETABLE TANNING MATERIALS. 47 

a very rational manner, so that the flesh of the bark remains 
intact, and produces, like the cork tree, new bark, which is per- 
iodically taken off. Snoaba bark contains 25 per cent, of tannin, 
and scorza rosa 13 to 15 per cent. The tannin colors ferric 
salts green, while it becomes brown by an addition of potash 
]ye. 

Ratanhy root is obtained from Krameria triandra, which 
grows in Peru. The root comes into commerce in a commi- 
nuted state, and is very rich in tannin, which is extracted with 
water, and the resulting solution used as an addition in tanning. 
The proportion of tannin is, according to Peschir, as much as 
42.6 per cent. It corresponds, according to A. Rabe,* with the 
formula C 20 H 20 O 9 . It is not a glucoside, and passes, by the 
splitting off of H 2 0, over into ratanhy red C 20 H 18 O 8 . 

Avens root, from Geum urbanum, contains, according to 
Trommsdorfif, up to 41 per cent, of tannin. Solutions of it have 
occasionally been used as an addition in tanning. 

Tonnentil root and Sassafras root show a still higher percent- 
age of tannin, the first containing, according to Gassincourt, 46 
per cent, of it, and, according to Reinsch, up to 58 per cent. 
Both roots being very expensive are not often used for tanning. 

Geranium wallichiannm is a new tanning material which 
grows in India and contains about 25 per cent, tannin. Leather 
tanned with it greatly resembles that tanned with canaigre, it 
being only somewhat darker. 

The wood of the Algarobia glandulosa of Gray, mesqaite oak, 
and Qnercus virens, live oak, contains much tannin in its entire 
mass, and is very successfully used in America in place of tan. 

Mimosa. — Besides the foregoing, the following tannins have 
been proposed and occasionally used : Barks of Butea frontosa 
and Butea gibsonis, both indigenous to the West Indies ; fruits 
of Balsomokarpon brevifolium\, bark of Eucalyptus; Pangue, a 
root growing in India; Pimica granatum, etc. 

In ChaptefsjkpCII andr XIII, we shall discuss the mineral tan- 
ning substancels^tf^l\ $- -~"*f w, k|J| 

* Pharm. Zeitung f. Russland, xix. 577. 

f Engl. Patentberichte, 1875, Ramsbacher, Masurer. 



CHAPTER IV. 

LEACHING ; THE BARKOMETER ; BARK MILLS ; BARK CONVEYER ; 

THE TAN PRESS. 

THE present generation need fear no scarcity of hemlock or oak 
bark. The question of the day, in the struggle for economical re- 
sults in the tanning industry, is leaching. Many tanners delude 
themselves with the idea that they are getting the best results 
possible considering the conditions under which they are work- 
ing, and by an occasional analysis of their spent tan they ap- 
parently prove their position. 

The results to be obtained must be admitted to consist in the 
extraction of a maximum amount of tannin with a minimum 
amount of water. It therefore does not follow that when the 
exhausted bark shows only one per cent of tannin, which is 
considered a good result, that the tannin taken out has been 
secured economically. 

There are at least four cardinal points to be considered in 
leaching, viz; ist, the character of the material to be treated; 
2d, a proper division to secure the best results ; 3d, the temper- 
ature and quantity of water; and 4th, the proper handling of 
the liquor. In addition to these are the minor questions of the 
shape and size of the leach, the handling and wetting of the 
bark, forced or gravity leaching and many other points. 

Many elaborate and expensive systems of forced leaching 
have been tried, and fairly, good results have been obtained by 
these methods — upward flow and downward flow, and all the 
other modifications that impractical ingenuity could devise. 

The more elaborate and expensive the system and the more 
patents and secrecy surrounding it, the better the results have 
been supposed to be. 

(48) 



LEACHING. 49 

It may be assumed that a system best for oak bark might not 
be the best one for hemlock or canaigre. Yet there are cer- 
tain general principles applicable to all which may be modified 
to suit the material to be treated, and the results are largely 
dependent on the skill and reasoning faculty of the operator. 

As a rule only one general system is employed by American 
tanners and extract makers and that is the gravity system. To 
advocate any other system, such as modifications of the diffusion 
process, involving the expenditure of large sums to violate the 
laws of nature, would necessitate the rebuilding of 99 per cent, 
of the leach houses in America ; therefore, attention will be paid 
to securing the best results under the system generally employed, 
involving as few changes in arrangement as possible. 

A man must fully understand what he has to do before he 
can determine the best way to do it. In the case of leaching 
we will assume an extreme condition to make the subject plainer. 
Suppose the bark, instead of being prepared in the usual way, 
is cut in pieces one inch thick and two inches square. It will 
be readily seen that if cold water is pumped on top and at the 
same time removed from the bottom, passing rapidly among 
and not through the pieces of bark, an immense quantity of 
water will be handled and yet the bark will practically never 
be exhausted. This is an extreme illustration of the most com- 
mon way of leaching. 

What we must do is to pass the water through the bark and 
not around it. We must regulate the temperature so as to se- 
cure the greatest solvency, therefore we grind or cut the bark 
and warm the water. Still, no matter how fine the bark or how 
hot the water, if the operation is rapid the solvent passes around 
the particles of bark and not through them ; therefore, slow 
leaching is absolutly necessary to secure maximum density in 
the liquor. 

If we have a leach filled with dry bark and water, or weak 

liquor is pumped on it, it at once goes to the bottom and does 

not dissolve or take up the tannin in the bark above it. This 

is another method of forcing the liquor around the bark instead 

4 



50 THE MANUFACTURE OF LEATHER. 

of through it; therefore, a leach when once filled with liquor 
should never be allowed to become dry or out of the liquor on 
top. There is a loss to be incurred in extreme slow leaching. 
The point of saturation must not be overlooked. A gallon of 
water at 6o° Fah. will hold in solution a definite quantity of 
tannin, sugar, salt, or other soluble matter and no more. At a 
higher temperature its solvent power is generally increased, but 
on cooling again the excess is thrown out of solution. Tannin 
and the other soluble principles of bark are heavier than water 
as shown by the barkometer or hydrometer. 

If we fill a leach with fresh bark properly prepared and then 
let in warm water and allow it to stand undisturbed for forty- 
eight hours — although at the beginning the conditions through- 
out the leach were uniform — we will find after this maceration, 
or soaking, that both the liquor and chips at the bottom of the 
leach are stronger than the liquor and chips at the top of the 
same leach. This result has been secured without a particle of 
expenditure of power or labor. If we remove slowly the liquor 
at the bottom, we gradually let the weak liquor at the top down 
on the strong chips below, and the top liquor should in turn be 
replaced with a liquor weaker than the bark to be treated. In 
this case we allow the solvent to pass through the bark and not 
around it, it becomes saturated with soluble matter, and no 
power or labor is expended until all has been accomplished that 
is possible. 

Therefore, this general rule may be laid down — for the head 
leach — no liquor should be removed from the bottom until it 
reaches the practical point of density and only so fast as it 
reaches this point. This may seem very slow work, but the 
point to be gained is not the securing of a large amount of weak 
liquor so much as a large amount of tannin. If we can get 
that tannin in the shape of liquor weighing 40 Twaddle, it 
is better and cheaper than to get four times the quantity of 10- 
degree liquor. 

The ideal leach should never be idle or dormant, nor should 
it be allowed to flow so rapidly as to be, figuratively speaking, 



LEACHING. 5 1 

" beating the air," or accomplishing results out of proportion to 
the power and labor expended. It should always be full of 
liquor in motion, until exhausted and ready to be pitched. The 
liquor in a leach should always be weaker than the bark to be 
treated. 

In a series of twelve leaches, we would start at No. I, sup- 
posing all to be filled with fresh bark. Fill No. I with weak 
liquor or water, allow to soak a few hours and pump from the 
bottom of i to the top of 2. As fast as the liquor reaches 
the practical point of saturation, remove to the storage tank for 
future use in the vats or pans, and pump the balance to the suc- 
ceeding leach, and so on. 

As the leaches are always full of liquor the pump lifts only a 
few feet and uses very little power. This is practically the Hol- 
brook system, which is however defective, in that the pump in 
each leach is operated by a common rod and all run at the same 
speed, owing to the fact that in a series of leaches no two are in 
the same condition. The speed of each pump should be regu- 
lated separately, which can probably be best done with an air- 
lift pump regulated by a valve. Jet pumps are objectionable 
because they reduce the strength of the liquor by condensation 
of steam and they will not handle hot liquors. 

In this way we have always a stream of liquor flowing on the 
top of each leach and a stream of stronger liquor from the bot- 
tom of the same to the succeeding stronger leach. From the 
head leach we have from the bottom a constant stream of sat- 
urated liquor and on the tail leach a constant stream of boiling, 
or hot water. We secure a maximum of tannin with a minimum 
of solvent, economy in hot water, labor and power. 

The most seriously defective and yet one of the most com- 
mon systems of leaching is found in houses having only one 
large pump, connected by water logs with the bottom of each 
leach. A wonderful show of work appears, but every accepted 
principle of leaching is violated — the liquors are all lifted the 
full height of the leach and from six to ten feet higher, they 
are jerked through the bark so rapidly as to make the use 



52 THE MANUFACTURE OF LEATHER. 

of enormous quantities necessary, strong liquor is forced over 
weak bark and gravity lost never to be recovered, fully double 
the boiler capacity is required and the final or finished liquor is 
not over one-third the strength that it should be. To pump the 
liquor from the bottom of any leach to the top of the same 
leach always involves a loss of power, labor and tannin — the 
bark should always be stronger than the liquor. It is more de- 
sirable to use one gallon of water to exhaust a given quantity 
of bark than to use ten, as well as very much cheaper. 

The Vaughn Machine Company, Peabody, Mass., now make 
leach pumps especially designed to do economical work. 

The latest mode of quick tanning uses borax to thoroughly 
cleanse the hide or skin of all impurities, thus making the tex- 
ture very open and receptive to the tannin, and then by using 
borax in the water employed for leaching, causes a very gentle 
fermentation of the bark, either oak or hemlock, so as fully to 
extract the tannin and allow it to enter into combination with 
the hide or skin without becoming in any degree crystallized. 

For grain, split buffed, patent, enameled, furniture, in fact 
any leather which requires a smooth split, there is no agent so 
good as borax, which can be used in the soaks and in the water 
employed for leaching the bark. The borax is used in the 
proportion of five pounds to the one thousand gallons of water, 
or a little more borax can be used if the water is very hard. 

The borax is first dissolved in boiling water and then added 
to the water under vigorous stirring. 

There is no patent on this system of leaching which we 
have advocated in this chapter, and it can be adopted in any 
leach house with slight expense. The question of regulating 
the temperature of the liquors is one of no little importance, 
and is dependent on the material to be treated. The tem- 
perature in a general way should be increased as the liquors 
become weaker. After the proper temperature for the head 
leach has been determined, the next weaker should be hotter 
and the temperature increased in each succeeding weaker leach 
until the boiling point is reached in the tail leach. As a rule 



LEACHING. 53 

very little heat is needed except for the tail leach, the liquor 
cooling as it goes forward and by the cooling of the liquor 
resins and other matter insoluble at low temperatures are 
thrown out of solution and are removed mechanically in pass- 
ing through the bark. Under certain conditions, as in winter 
weather, when the liquors cool too rapidly it is convenient to 
have a steam coil of copper pipe in the bottom of each leach 
below the false bottom, so a little steam can be used if necessary 
to keep the liquor up to the proper temperature. 

Extract manufacturers claim to secure larger yields of tannin 
from their bark than tanners, and doubtless in a general way 
they do, as their attention can be concentrated on this one 
point, but waste never profits any one and economical results 
benefit all. 

The proper leaching of bark, although apparently a difficult 
problem, is really a simple one when once understood. Much 
of the difficulty experienced is brought about by the lack of 
proper checks and records when a new experiment is tried. 

The difficulty does not end here, but is still further magnified 
by erroneous conclusions. For example, an experiment is tried 
and proper precautions are not observed in getting the data ; 
so called insignificant matters are ignored, although the success 
of all experiments depends upon them, and at the end of the 
experiment we review such data as we have, and immediately 
conclude that this or that system is wrong or right, when in 
fact by taking into account so called insignificant matters the 
conclusion is just reversed. 

It is a well known fact that a soluble body, or one enveloped 
in a body which is hardly soluble, will dissolve much more 
quickly in a fine state than if it were in a large piece or pieces. 
For instance, granulated sugar will dissolve much more rapidly 
in water than will rock candy, although both are identical and are 
only presented in different physical states. We have an analo- 
gous case in bark, large pieces of ground bark corresponding to 
the rock candy and finely ground bark to the granulated sugar. 
But it must be observed that water will dissolve just as much in 



54 THE MANUFACTURE OF LEATHER. 

either case if given sufficient time ; that is, the rate of solution 
is slower or more rapid, as the case may be. Water will pene- 
trate to a certain depth in bark in a given time, and dissolve a 
certain amount of soluble matter. It will also take a definite 
time for this solution in the bark to diffuse into the surrounding 
water. It will be granted that the finer the bark the more rapidly 
will this diffusion take place. Knowing the above facts, it is 
evident that fine bark will leach more perfectly in a shorter 
space of time than coarse bark. It is well known to tanners 
that it is impossible to leach the bark, or to get any liquor 
through the mass of bark in the leach, when the bark is ground 
too finely, and when the old system of draining or pumping off 
is used. 

This difficulty of packing may be overcome by always keep- 
ing the leach full of liquor, so as to keep the bark floating and 
allow the liquor to pass evenly through it. It is possible, how- 
ever, when the leach has packed to force the liquor through the 
mass of bark with pressure, such as is used in the diffusion sys- 
tem. It even then happens that the leach or cell packs, and it 
is then necessary to reverse the pressure to partially loosen the 
mass and facilitate the circulation. But it is never possible to 
bring about the proper circulation when once' the leach or cell 
has packed. But why should an unnecessary amount of com- 
plication and expense be added when it is possible to accom- 
plish the same results in a much more simple manner? This 
can be done in the following way : The bark is comminuted as 
finely as possible ; that is, it should be either cut, shaved or 
shredded, rather than ground to a dust. The bark so prepared 
is conveyed to the leach, which, when full, is properly levelled 
off and covered with boards, which, in turn, are held down with 
two heavy pieces of timber slipped under cleats fastened to the 
sides of the leach near the top. The bark, therefore, is held 
down when the leach is full of liquor. The leach is now filled 
with water or weak liquor and when full it can be pumped off 
at once, but it is preferable to allow it to stand over night. 

The pumping is done from the bottom of the leach through 



LEACHING. 5 5 

a copper or brass tube which extends to the top. This pump- 
ing is so regulated as to draw off just as much liquor as is run 
on the top, so as always to keep a sheet of liquor six to twelve 
inches deep on the top of the bark. This sheet of liquor plays 
an important part and really determines the success of the leach- 
ing, as the liquor follows directly, without channeling, and takes 
the place of the stronger liquor which has gone before it when 
the leaching is in progress. The result is that the great factor 
" percolation " is taken advantage of. The pumping is continued 
until the liquor is reduced to a point where it cannot be used 
in the tannery. The liquor is then pumped on to a fresh leach 
which is treated in the same manner as the first, which has just 
been described, and so on through the whole series of leaches. 
The number in a series should run from ten to twelve or more, 
depending upon the depth of each leach. 

It is well known that the longer the column of bark through 
which the liquor passes the stronger is the liquor and more 
perfect the leaching. But there is a limit to the length of the 
column in any one leach, as when we exceed a certain depth, 
say ten or twelve feet, we interfere with the circulation, or, in 
other words, the bark packs and we experience the difficulty 
alluded to above. In order to get the benefit of the long col- 
umn we take advantage of the number of leaches, as we can 
thereby increase the length of the column to any extent 
desired. 

The advantage of ten or more leaches is apparent when the 
density of the liquor is taken as it comes from each pump. It 
will be found that the difference between the tail leach and the 
one next to the head will be from one to one and a half degrees 
for every leach. For example, suppose there are twelve leaches ; 
the water leach will show one degree and the eleventh leach 
from eleven to sixteen degrees barkometer, and so on. 

By observing the above precaution and following the method 
described, it is possible to make a stronger liquor of the same 
quantity than under the usual conditions. In other words, we 
get the same amount of tanning substance in a more concen- 
trated form, or we will complete our leaching with less water. 



56 THE MANUFACTURE OF LEATHER. 

Attention should be called to the fact that efficient leaching 
cannot be done with cold or merely warm water or liquor. It 
is necessary to apply the water or liquor on the tail leaches as 
hot as it can be made, say from 205 ° to 212 F., and to work 
the leaches actively. 

It will be found that the liquor from the head leach, after it 
has been pumped down in density until it is ready to go onto a 
fresh leach, registers from 110° to I20°F. It is now advisable 
to pass it through a heater — especially during the winter months 
— before putting it on the fresh leach. The liquor should have 
such an initial temperature that it will register about 95 ° to 
ioo° F. after having passed through the fresh bark. 

It will be found that by working according to these temper- 
atures, about 950 gallons of a 22 liquor, barkometer at 6o° F., 
containing about 2.75 per cent, tanning substance, can be ob- 
tained from 2,000 pounds of bark, which means that we have 
extracted about 90 per cent, of the tanning substance of the 
bark. On the other hand, if the temperature of the liquor is 10 
to 15 degrees lower, the quantity of liquor will be reduced from 
20 to 25 per cent. 

It will be found when the density of the liquor coming off the 
head or fresh leach is noted every five minutes — proper correc- 
tion being made for the difference of temperature — that the 
density falls regularly. 

If the figures so obtained be platted on paper — paper ruled 
in squares, called platting paper, such as engineers use, — it will 
be found that the fall in density follows a curve which is nearly 
a parabola, such as theory indicates. 

The most convenient and accurate check on the efficiency of 
the leaching is the measuring and weighing, that is, taking the 
density of the liquor from each leach. 

The liquor should occasionally be analyzed, to show whether 
the ratio of tanning substance to the degree of barkometer var- 
ies, and to what degree. Any variation should be allowed for 
in the calculation for the efficiency of leaching. 

It might be said that just as efficient leaching can be done 



LEACHING. 5 7 

when the bark is not cut or ground so fine, by giving longer 
time. Tanners will submit as a proof the analysis of the " spent 
bark" according to which there is more tanning substance in 
the coarse than in the fine spent bark, which has been leached 
in a much shorter space of time. 

It is not k7iown, however, that the difference between the fresh 
and spent bark (coarse) is in the liquors in an available form. 

It will be found when the liquors from the coarse bark are 
measured — just as from the fine bark — that the quantity is con- 
siderably less. That is, the amount of tanning substance really 
in the liquors falls short, and the efficiency of leaching is not so 
great. 

It may not be generally known that bark in the lyaways loses 
comparatively little of its tanning substance in two or three 
weeks while in the liquors. It cannot be said that the reason 
of this is that the liquor is as strong as the bark, because in 
putting just as strong or even a stronger liquor on a fresh leach 
we get a proportionally stronger liquor. So there is something 
else beside simply soaking. When a warm or hot liquor is put 
on a leach and left to stand, the temperature of the top liquor 
falls very rapidly. 

When this cold liquor passes down through the bark it re- 
duces the temperature, so that it is alternately heated and cooled, 
which is fatal to perfect leaching, as the temperature of bark 
and liquors should be steadily increased toward the tail or wa- 
ter leach. The only way to do this properly is to work the 
leaches actively. Leaches ought to run day and night. 

Some tanners still advocate putting the spent liquor from 
"rockers" on the tail leach. The very small amount of tan- 
ning substance saved (such liquors do not contain at the utmost 
over one-half of one per cent, and usually from two-tenths 
to three-tenths per cent, of tanning substance) is completely 
overbalanced by the large amount of filth, non-tanning sub- 
stance, etc., always present in such liquors. 

What is the object of applying a mellow liquor, weak in tan- 
ning substance, to a green hide from the beam house? It is to 



58 THE MANUFACTURE OF LEATHER. 

purge it of the lime and filth. If we are so anxious to get rid 
of these on the one hand, why should we take particular care 
to recover them, as it were, on the other? 

The lime which is kept in solution by means of the organic 
acids present in the liquor, is partially precipitated in the bark 
as soon as the acid is absorbed by it. The consequence is that 
there is considerable tanning substance fixed which cannot be 
extracted later on. 

At any rate, it is now apparent that it is better and more 
economical to run this liquor away, and instead put nothing but 
clear water on the leach. We shall then not only get the same 
amount of tanning substance, but in a more desirable form, as 
non-tanning substances, such as exist in spent liquors, are car- 
ried forward unchanged in the leaches. 

The last system of leaching bark which has been described in 
this chapter is in use by the American Oak Leather Co., Cin- 
cinnati, Ohio, and the plant was built by Byron Holbrook, 
Milwaukee, Wis. The leach house of the American Oak 
Leather Co., is the most modern in the world, about $25,000 
having been spent on it. 

Stephen Dow & Co., and E. C. Cottle & Son, Woburn, Mass., 
and Beggs & Cobb, Winchester, Mass., have recently put in new 
systems of leaching hemlock bark. The leaches are circular 
in form, 12 feet in diameter and 14 feet deep. There is a bark 
conveyer overhead and a conveyer underneath for the spent 
tan, leaving the leach house clear of obstructions. 

The water that goes on the head leach is about 140 F. in 
temperature, but the water that is put on the tail leaches is at 
212° F. 

Tanners who use bark are paying greater attention than ever 
to their leaching systems. The depression in business and lack 
of profits is forcing manufacturers to economize in every direc- 
tion, and save all that is possible in their processes. Many 
tanners are now convinced that it is better to replace old leaches 
and faulty methods by modern improvements, rather than de- 
ceive themselves with apparently saving expenses by sticking 
to superseded and wasteful methods. 



LEACHING. 59 

Tanners with old-fashioned square leaches, set in the ground, 
which have to be laboriously thrown out when spent, are now 
building the popular round leaches, placed above ground, and 
supplied with openings at the bottom, through which with little 
effort a man can quickly feed the spent tan to the conveyer 
under it. 

There seems to be much more inclination among tanners to 
pump their leaches more frequently. Careful foremen state 
that the best way is to keep the ground bark covered with liquor, 
and in this manner prevent channels being formed in the leach. 
Bark ground finely is particularly apt to pack, unless pumped 
over carefully and properly. It is said that if a leach is simply 
pumped off and then refilled, channels are more liable than when 
there is a good head of liquor on the top of the leach, which 
percolates evenly, and is as evenly replenished at the top. 

Some tanners prefer flooding. Of course, to enable the pumps 
to be kept working constantly, a certain amount of liquor has 
to be thrown into storage tanks. Those who are leaving the 
least percentage of tannin in their bark say they put moderate 
heat on the new or head-leach, but that the other leaches get 
red-hot liquor all the time. A successful oak sole leather tan- 
ner claims to get 1,000 gallons of 22 degree liquor from 2,000 
pounds of oak bark. When asked how many pounds of oak 
leather he made from a cord of bark, he retired into eloquent 
silence, feeling that his chief success in meeting competition lay 
in his ability to manufacture in the most improved manner at 
the lowest cost, and to keep his own counsel. Numbers of tan- 
ners are leaching to-day exactly the same as 20 years ago. 
They simply pump one leach into another in rotation and not 
simultaneously, and let it go at that. It is now generally ac- 
cepted, however, that more can be obtained from bark by hav- 
ing pumps in each leach, and keeping all of them actively at 
work all day and all night. 

The grinding of bark is being done much more carefully than 
formerly. Some tanners screen their bark after grinding, and 
throw all coarse pieces into the mill again. Unless bark is thor- 



60 THE MANUFACTURE OF LEATHER. 

oughly and properly ground it will not leach as it ought to. It 
is expensive and wasteful to operate poor mills and poor leach- 
ing systems. Better for tanners to keep up to date, to incur the 
expense attendant on improvements, and thus be in line for 
making leather under the best conditions, and at the lowest 
cost. 

The most enterprising tanners keep a ledger account for each 
leach. They weigh the bark before grinding, and measure the 
liquor produced. All this means careful watching and figuring. 
But it also means stoppage of leaks, and as well as an intimate 
knowledge of results that are actually obtained. The path from 
a fool's paradise to the bankruptcy courts is being trodden every 
day by weary feet. Chemical analysis has rudely awakened more 
than one tanner to the true condition of his affairs in his leach- 
house and elsewhere. If a tanner is satisfied that he is properly 
exhausting his bark, he should be all the more willing to get a 
chemist's endorsement of his success. Possibly, however, he 
may find that after all he was leaving a percentage of tannin 
which might have been saved. There is undoubtedly a wave 
of reform in leaching systems, but it is equally true that many 
tanners are still laboring in old wasteful ruts. Only recently 
an oak leather tanner confessed that the oak bark that he 
dusted into his layaways contained much more tannin after 
being cast out than he imagined. He awoke to the fact that 
by dumping this bark into a tank and using hot liquors, he was 
able to exhaust it much better than by simply using cold runs. 

What with liquor heaters and coolers of excellent design on 
the market, cheap pumps and good bark mills, there seems to 
be no reason why those tanners who claim to be leaving only i 
per cent, or less of tannin in their bark should be as few as they 
are at present. 

One of the best methods for leaching tanning material is that 
known as the Press-leach system. For oak bark it is specially 
suited. Any number of leaches up to 12 may be taken to con- 
stitute a set. For example, let us take a set of six, which may 
be arranged in a row of six, or in two rows of three side by 



LEACHING. 6 1 

side, and fill each with bark. Each pit leach is fitted with a 
false bottom raised about 6 inches from the bottom of the pit, 
through which liquor but not bark may easily pass. A pipe or 
trunk connects the bottom of No. I pit to the top of No. 2, and 
the whole series is in the same manner connected, so that 
the liquor passes through each pit of the series on to the top 
of the next stronger. The liquor from No. 6, the strongest, 
may be used for the pits. Water or weak liquor is run on to 
No. i and slowly percolates through the bark, passing on to 
the top of No. 2, and so on up to No. 6, gaining in strength as 
it advances. By this means the most perfect leaching is ac- 
complished, though in practice it is found difficult thoroughly 
to spend bark. Before No. i is cast, it is necessary to run 
on one or more hot waters. This dissolves a large amount of 
"reds" and resinous matters, together with the rest of the 
tannin, but as the liquor passes through the succeeding pits, 
which cool down, the reds and resinous matters separate out, 
and are filtered off. A copper coil under the false bottom of 
each pit through which steam may be passed is also beneficial. 

When the material in No. I is spent, it is cast and filled with 
fresh bark, and becomes the best leach, and is connected to No. 
6, No. 2 becoming the spender, and in this manner each pit in 
its turn becomes the hinder pit. By this system a constant 
stream of water or weak liquor is run on the top of the weakest 
pit, and a stream of the strong liquor may be taken from the 
bottom of the strongest. It saves much labor, pumping, etc., 
and gives better results than some other systems. A little care 
must be taken in packing the bark — packing loosely, so that 
the liquor may flow easily and avoid clogging or channels. 

The system which we have described in the earlier part of 
the chapter is considered by the American tanners to be an 
improvement on the above, and certainly presents great ad- 
vantages. The liquor, instead of being allowed, by finding its 
level, to flow from one pit to the other, is pumped over by an 
air lift pump attached to each pit, thus keeping the levels in 
«ach pit the same. It is important never to let a leach run dry, 



62 THE MANUFACTURE OF LEATHER. 

as the material by so doing sinks down and becomes sodden, 
and is liable to heat, and prevents proper percolation. 

THE BARKOMETER. 

In the use of the hydrometer, or barkometer as it is com- 
monly termed by tanners, it must be kept in mind that it is de- 
signed simply to determine the density of any fluid more dense 
than water, as compared with pure water. It does not indicate 
of what the fluid consists ; the density, or specific gravity, of 
other heavy fluids can be shown just as readily as that of a 
solution of tannin, and be indicated on the stem in the same 
way. The purity, or comparative purity, of a tanning liquor 
being known, the barkometer will show its comparative value. 

The barkometer is graded so that when it is placed in water 
at 6o° temperature it will stand at O , and the tanning liquors 
to be weighed by it should be at the same temperature ; but as 
fluids contract and expand largely as they are cooled or heated, 
if the liquor is warmer than 6o°, the barkometer will indicate 
less density than it should ; if colder, greater density. This 
shows the value of a thermometer, to be used in connection 
with a barkometer, as the sense of touch cannot be relied upon 
to indicate the degree of heat. Barkometers made of glass are 
more reliable than any others, for they expand and contract 
less, and although in preparing the liquors it is not uncommon 
also to judge of their strength by the taste, still this is not a 
good guide, and no tanner can afford to be without a barko- 
meter. 

It is perhaps necessary also to remark that this instrument 
is applicable only to freshly-made liquors ; for otherwise con- 
fusion and want of confidence might ensue upon finding that it 
sinks, sometimes, to a corresponding degree in spent liquor, 
and which is owing to the fact that the alterations which 
tanning liquors undergo during use and exposure may not 
diminish their density, though they impair and destroy their 
tanning power. 



LEACHING. 63 

BARK MILLS. 

Oak and hemlock bark are the standard tanning materials of 
the United States. In Europe and other foreign countries the 
following materials are principally used — valonia, myrabolans, 
gambier, sumac, divi-divi, mimosa bark, quebracho, bark of the 
oak, fir and less important trees, and bark extracts. The 
manipulation of bark so that its tannin can be extracted is a 
problem that has attracted the attention of many ingenious 
minds. Numbers of patents have been secured for machines 
and appliances for peeling, rossing, cutting, grinding, crushing 
and rolling bark. 

In days gone by, when bark was plentiful, it was lavishly and 
wastefully used. It is not more than ten years ago since even 
the best tanners in this country were getting much less tannin 
from their bark than they are to-day. 

Bark is liable to be placed before the tanner in three differ- 
ent conditions — dry, damp or green. These differences have 
called forth special methods for handling bark in any stage to 
the best advantage. Many theories have been advanced in 
regard to the best methods of preparing bark so that its tannin 
can be most thoroughly extracted. 

A study of the Patent Office reports, relating to the machines 
and appliances for reducing bark, is very interesting. It is to 
be regretted that the very old records are so bare of details. 
They simply mention the date of the patent and the name of the 
patentee. Modern reports from the Patent Office give as full 
information in regard to patents as could be desired. A some- 
what melancholy history is attached to the various bark mill 
patents. One can easily imagine the "big thing" that the in- 
ventors thought they possessed in patents which have been 
forgotten long ago. We suppose many of the inventions did 
good service in their day, and did not sink into obscurity with- 
out yielding some compensation to those who thought them 
out. 

The earliest patent for a bark mill is dated October 25, 1826, 
and was awarded to C. Foss. This machine consisted of six- 



64 THE MANUFACTURE OF LEATHER. 

teen knives on a swiftly revolving wheel. It certainly cut the 
bark, but in a crude and wasteful manner. It is instructive to 
recall this patent, remembering that we have bark cutters to-day 
that work on the same principle, although vastly improved in 
every respect. In 1828, A. Bull received a patent for a bark 
mill. This was on the segment plan which is so familiar to-day. 

Then followed a number of inventions for breaking the bark 
in different ways in a hopper, from which it fell between metal 
teeth or segments arranged in different ingenious ways to pul- 
verize the bark, and render it easy for leaching. 

The main object of tanners is to break up the bark so that 
the tannin-cells can be easily dissolved by water or weak 
liquors. At present there are two leading methods of grinding 
or reducing bark. Many tanners advocate what is called the 
Beecher system of grinding between segments. Other tanners 
favor cutting or shaving, to reduce the bark into shreds which 
can be readily leached. A few years ago attention was called 
to bark-rolling machines. The idea was to take freshly ground 
bark, and to place it under heavy metal rollers, so that the bark 
cells could be flattened out and in a way that would yield their 
tannin easily when soaked. It took so much power to drive 
these rollers that their use has been confined to comparatively 
few places. 

There have been fads in the bark business just as in every 
other line. Many years ago it was considered wise to remove 
the ross or outside covering from the bark before it was ground 
in the mill. Elaborate theories were advanced proving that 
the flesh or part of the bark next to the tree containing the 
tannin would be more profitable to use by itself in the leaches. 
It was found, however, that the time and trouble necessary to 
take off the ross was not repaid by results. Tanners acknowl- 
edge to-day that while the ross of the bark is not a tanning 
agent, it contains certain properties when ground in with the 
flesh of the bark that help to make good leather. Besides, the 
value of ross as fuel is no small item in a large tannery. We 
can well recall the time, some twelve years ago, when O. K. 



LEACH INQ. 



65 



Lapham, who then lived in Chicago, introduced Dr. H. E. 
Starcke to the tanners of the United States. Mr. Lapham was 
a student of the properties of bark, and in common with James 
E. Mooney and the late Jackson S. Schultz, he employed 
this young German chemist to analyze some alleged " spent 
tan " from leading tanneries. The analyses startled and aroused 
the tanners, who were disposed at first to doubt their accuracy. 
The chemist's science, however, stood the tests brought against 

Fig. 4. 




FRONT VIEW. BARK CUTTER. — (JONES' PATENTS.) 



it, and an era of reform was inaugurated in the manipulation of 
bark which is still active to-day. With improved bark mills, 
and a better understanding of the .methods of leaching, much 
less tannin is wasted than formerly. There is still, however, 
room for improvement in the latter direction. It would seem 
almost impossible to surpass the machines now on the market 
for grinding or cutting bark. 
5 



66 



THE MANUFACTURE OF LEATHER. 



Bark mills are manufactured by Ott's Bark Shaving Mill Co., 
La Crosse, Wis. ; Byron Holbrook, Milwaukee, Wis. ; Eureka 
Bark Mill Co., Lancaster, Pa. ; W. F. Mosser & Son, Allentown, 
Pa., and Shapley and Wells, Binghamton, N. Y. J. T. Phillips, 
Grand Rapids, Mich., makes a disintegrator which is valuable 
to bark users, and is claimed to furnish results not to be had 
by the use of any other machine on the market. 

We show in Figs. 4 and 5 a front and rear view of a bark 

Fig. 5. 




REAR VIEW. — BARK CUTTER. — (JONES' PATENTS.) 

cutter made by the Vaughn Machine Company, Peabody, Mass., 
and which is largely used by tanners in all parts of this coun- 
try and in many parts of Europe. 

A prominent tanner writes the builders as follows : " That 
after a thorough test of four months with the cutter they are 
satisfied that it better prepares the bark for leaching, and gives 
better results in every way, than any other machine they have 
known in 35 years' experience as tanners." 



LEACHING. 67 

In construction it is simplicity itself, with no gears, chains 
and apparatus to get out of order. There are two discs, the 
front or breaking disc revolving, and the rear or fine cutting 
disc stationary. The bark is thrown into the hopper in front 
by armfuls, when the revolving disc, in which are set six 
knives, cuts or breaks it up into small pieces, which then pass 
through compartments in the revolving disc onto the face of 
the rear disc, around which it is carried until cut up fine by 
the twenty knives which are set in this disc, and passed 
through the small throats or apertures in which these knives 
are set, and falls down into the conveyer at the rear of the 
same. All practical tanners will see that the bark being cut 
up into small pieces by the first disc, before reaching the knives 
where it is cut fine, it is impossible to get large shavings, which 
cannot be avoided in any other w r ay. 

One excellent feature also is that the rear or stationary disc 
is made sectional, there being five sections with four knives 
in each one, so there is absolutely no trouble nor time lost in 
sharpening, as each mill is fitted with two complete sets of 
sections and knives ; thus, when the knives become dull, the 
sections can in a few minutes' time be taken out and replaced 
with the sections containing sharp ones, which virtually gives 
the purchaser the wear of two mills, as the sections are the 
principal parts that will wear out. This cutter is strictly port- 
able and costs very little to set up ; no more in fact than for 
an ordinary machine, as it has simply to be bolted down to the 
floor over the conveyer or elevator shute, and belted onto from 
a countershaft above. 

Solidity is another feature the builders claim, and any tanner 
will appreciate that point and to get a bark cutter that will not 
break nor get out of order easily. 

The weight complete is 4000 lbs.: speed from 250 to 300 
revolutions per minute. Pulley used 36 inches diameter, 12 
inches face. Dimensions : 6 ft. long, 4 ft. wide, 4 ft. high. 

Capacity : The builders claim for it 30 cords per day, wet or 
dry, and guarantee that the quality as well as the quantity done 
will suit the most exacting. 



68 THE MANUFACTURE OF LEATHER. 

In Fig. 6 is shown the new automatic knife grinder for the 
Jones patent bark cutter and other cutters. It weighs only 
700 pounds, and is simple, durable and effective. 

Emery wheel made special and can be run dry or in water 
as preferred. Warranted not to heat or draw temper of the 
knife. Sizes: 32 inch, 36 inch, 50 inch. Emery wheel, 22 

Fig. 6. 




AUTOMATIC KNIFE GRINDER. 



inch diameter, 1^ inch face. Driving pulleys, 10 inch diam- 
eter, 3 inch face, tight and loose, and warranted to run 140 
revolutions per minute. This machine is built by the Vaughn 
Machine Company, Peabody, Mass. 

BARK- CONVEYER. 

This invention, which was patented May 1, 1883, by Mr. 
Oliver A. Zane, of Peabody, Massachusetts, relates to the end- 
less chains and lags or devices connected therewith for convey- 
ing bark or various other matters from one position to another, 
it being specially useful for what in tanneries are termed 



LEACHING. 



6 9 



"ground-bark conveyers," each of which in the main consists of 
an endless chain and a series of lags or bars, such lags or bars 
being arranged at equal distances apart and fixed or held to the 
chain, and the latter being extended around and supported by- 
two spider or sprocket wheels. The conveyer so constructed is 
arranged to extend within a trough, through which, lengthwise 
of it, the chain in moving drags the lags and causes them to 



Fig. 7. 




Fig. 8. 




Fig. 9. 




Fig. 10. 




Fig. 11. 




force along with them the bark or material to be transferred 
from one position to another or higher one. 

Fig. 7 is a top view, Fig. 8 a longitudinal section, Fig. 9 a 
side view, and Fig. 10 a transverse section, of part of a conveyer 
containing Zane's improvement. Fig. 11 is an edge view of 
one of the links of the endless chain of such conveyer. Fig. 12 



7o 



THE MANUFACTURE OF LEATHER. 



is a rear elevation, and Fig. 13 a front elevation, of one of the 
lags of the conveyer. 

Previous to this invention it had been customary to construct 
certain links of the chain with ears extending from them and 
formed as shown in Figs. 14 and 15 at a a, the lag being fast- 
ened to the link by screws passing through the ears. These 
ears are very liable to become broken from the link, and 
thereby render it useless, and to necessitate the substitution of 
another, frequently at considerable expense, inconvenience, or 
loss to the tanner. With this invention the links of the chain 
are all alike and require no such means of connection of any of 



Fig. 12. 



3 



1 



Fig. 13. 

? * V 



Fig. 15. 



? 



s=?5_ 



Fig. 14. 




them with a lag, which may be attached to any one of them 
throughout the chain. In Figs. 7, 8, 9, and 10, these links are 
shown at A A A and a lag at B. Each link tapers lengthwise 
and crosswise ; or, in other words, it is not only dovetailed in 
form lengthwise of it, but is also dovetailed transversely of it, as 
represented. It is hooked, as shown at c, at one end to clasp 
the cylindrical end part, d, of the next link, each link being 
notched as shown at e and g, to enable it to be coupled with 
or uncoupled from another link. The lag B has made in it a 
notch or recess, f, to receive a link, such notch or recess being 
tapering or dovetailed both lengthwise and transversely of it to 
receive and fit to a link, which, previous to being engaged with 



LEACHING. 71 

its two next adjacent links, between which it is to extend, is to 
be placed within the notch or recess. Instead of this double 
dovetailed notch or recess being formed immediately withfn the 
bar or lag, it may be in a block or piece of metal screwed or 
fastened to the lag. While the dovetails of the link will keep 
the lag from slipping off the link in one direction transversely 
and in another lengthwise of it, the next link, by extending 
transversely beyond the lag-link, as shown, will prevent the lag 
from slipping off its link in the opposite direction longitudinally 
of the link. Thus by having to the lag a double dovetailed 
recess or link-socket, as described, and by having the chain- 
links made as represented, it is possible not only to readily 
adapt a lag to any link of the chain, but also to keep it in place 
without any screws, ears, or other fastenings, as heretofore 
employed ; and when a tanner is provided with auxiliary links 
he can, in case of breakage of any one of the chains, readily 
supply its place with another. 

Instead of a lag, a bucket may be used, and be provided 
with a double dovetailed recess or link-socket, as described, to 
receive a link of the chain. 

THE TAN PRESS. 

The machine shown in Fig. 16 is made by William F. Martin, 
Salem, Mass., and is indispensable in every well equipped 
tannery, for the preparation of the spent tan for fuel. The 
machine is compact, simple in construction, and easily kept in 
order. Ten cords of wet dripping tan can be run through the 
press in a day, pressed dry, and it is ready to burn under the 
boiler without the addition of coal or any other fuel. At this 
late day it is perhaps unnecessary to speak of the economy of 
a tan press over drying the tan in the sun, or over the boiler, 
or having it carted away as waste. Suffice it to say, that no 
tanner who has used a press would think of doing business 
without one. 

Yet as some tanners are still doing business without a press, 
it may be said to them that the economy of one is this : That 



72 



THE MANUFACTURE OF LEATHER. 



by the means of an elevator, consisting of buckets on an end- 
less chain, the spent tan is taken from some convenient deposi- 
tory near the vats or leaches, to a bin above the tan press. It 
feeds itself through, and is from there deposited in front of the 
boiler, where it is ready to burn, thereby saving all labor except 
the little of getting the tan to the place where it is first taken 

Fig. i 6. 




SALEM ROTARY TAN PRESS. 



up by the elevator. Thus is there a good fuel convenient for 
use at almost no cost. 

Diagram of press is shown in Fig. 17. After the tan has 
been thrown into the hopper D it is then forced by the fluted 
feed roll B through the pressure rolls A A, and sliding down 
delivery plate E, it falls in front of the boiler ready to be 



LEACHING. 



73 



shoveled into the furnace. The water is taken care of by the 
revolving brass strainer roll C. 

The press is run by a 4 in. belt, requires but little power and 
should be run at a speed of 75 revolutions. 



Fig. 17. 




DIAGRAM OF TAN PRESS. 



CHAPTER V. 

TANNING EXTRACTS. 

The use of extracts in tanning has grown to large propor- 
tions during the past fifteen years. There are many advantages 
in the use of such extracts. The liquors are always under per- 
fect control, that is, by putting in so much extract the quan- 
tity of tanning material is known. It does away with the 
storing of large quantities of bark, as one barrel of extract is 
equivalent to about one cord of bark — 128 cubic feet. Where 
space costs money this is quite an item, and it also saves inter- 
est and insurance on the bark. 

There is no difference in the fibre produced by bark liquors 
and pure tanning extracts, as properly prepared extract is 
nothing more than concentrated liquor. Tanning extracts in 
common use in the United States are made from chestnut oak 
bark, chestnut oak wood, chestnut wood, hemlock bark, quer- 
citron bark, canaigre and sumac ; black oak bark extract is 
used to give a bloom to leather, and coloring or dyeing extracts 
are made from logwood, fustic and from a large number of 
other materials. 

The chestnut tree, after it is felled, is peeled of the bark, 
which is objectionable on account of the coloring matter which 
it contains. The chestnut oak tree is used as it comes from the 
stump. The chestnut tree and the chestnut oak tree are cut 
into suitable lengths, say about four feet long, in the forest. 
These pieces are then carried to the factory, where they are 
further reduced by "chipping" by a machine built especially 
for the purpose. This machine is a cast steel disk four feet in 
diameter, revolving rapidly and carrying a suitable arrangement 
of knives, which cut the wood into small chips. These chips 

(74) 



TANNING EXTRACTS. 75 

are carried to the leaches and leached or extracted as is usual 
in tanneries. No chemicals should be used in the leaches. 
The liquor is then run into settling tanks, and next passed 
through ten wire cloth strainers of the finest meshes to clarify 
it, after which the liquor goes to the vacuum pan and is con- 
centrated under diminished pressure at a temperature of be- 
tween 120° and 140 F. 

The above described method of settling and straining is the 
one in common use in the United States, and it produces a 
liquor which is pure and transparent enough to be made into 
an extract suitable for tanneries. 

When the degree of heat has been carried too high in the 
leaches, such liquor can only be clarified sufficiently by 1st. 
Lowering the temperature below the coagulating point of blood 
and adding blood ; 2nd. Raising the temperature of the liquor 
sufficiently high to coagulate the blood, which gathers up the 
fine suspended matter and settles to the bottom of the vat or 
tank, and is then still further strained. It is then concentrated 
as usual. 

Extract, however, made from a liquor which has been pro- 
duced at too high a degree of heat — although clarified by blood 
albumen — will not produce a satisfactory article ; that is, such 
an extract is not strictly speaking a concentrated liquor. 

The extract maker, it is true, obtains a larger yield or num- 
ber of pounds of finished extract from his material ; but it is at 
the expense of the tanner. The excessive degree of heat in the 
leaches extracts not only non-tanning substances, which are 
objectionable, but destroys also certain bodies which act favor- 
ably in the production of leather. 

In the concentration of the liquor in the vacuum pan extreme 
caution must be observed as to the degree of heat. A temper- 
ature of over 140 F. or thereabouts produces a change in the 
tanning substances and in its allied non-tanning substances, 
which is very objectionable, and which produces an undesir- 
able leather, not only in color but in quality. In other words 
a liquor although carefully made, when subjected in the pan to 



j6 THE MANUFACTURE OF LEATHER. 

a degree of heat in excess of 140 F. or thereabouts, yields an 
extract, which, when diluted with water, is not what it was be- 
fore concentration. It is on this account that the multiple 
vacuum pans — that is, more than one pan — can not successfully 
be used in the concentration of liquors or the making of ex- 
tracts. 

In the use of extracts the tanner should always be on the 
lookout for only the pure article, free from adulterations of any 
kind. Extract is now being used extensively for sole, upper, 
belting, harness, union, enameled and patent leather, and in 
nearly all the cases which have fallen under our observation 
giving good results in both tannage and weight. 

There are various methods followed in the preparation of 
hemlock extract, but that used by a prominent extract com- 
pany in Pennsylvania is a good one. The bark is ground in 
the old-fashioned mill, and is very carefully leached in the old- 
fashioned way and boiled down in the vacuum pan under the 
least degree of heat that can be employed. No chemicals 
whatever are used. They do not press or crush their bark to 
get from it a larger yield, but are doing their best to give a 
pure article which will produce a pure, strong, old-fashioned 
liquor. They take a good, fresh io° barkometer liquor and 
boil it down to 27*^° Baume in vacuum. There is no other 
description than this, for this is all they do. 

The boiling point of water varies according to the pressure. 
With a pressure of 29.2 inches, it boils at 21 2°; with a pres- 
sure of 27.74 inches it boils at 208 F. In a vacuum water will 
boil at 6j° F. Advantage is taken of this fact in the extrac- 
tion of sugar. The application of heat in the ordinary way 
converts a large quantity of crystallizable sugar into an un- 
crystallizable state, thus causing a serious loss. By effecting 
the concentration in a vacuum it takes place in a much lower 
temperature and prevents this source of loss. 

The manufacture of tanning extracts now closely resembles 
the process for extracting sugar; the sliced wood is exhausted 
by diffusion in autoclaves under slight pressure, and the liquor 



TANNING EXTRACTS. 7 "J 

is filter-pressed and evaporated in some cases in triple-effect 
apparatus which differs from those used at the sugar works 
merely in being constructed entirely of copper and bronze, to 
the exclusion of iron, and in being worked at a higher vacuum 
than sugar pans are. Most manufacturers decolorize the liquor 
before concentration, either by the addition of some metallic 
salt or with albumen and bisulphite of soda. In the former 
case the acid of the salt remains in the extract, and in the 
latter sulphate of soda and non-coagulable albuminoids are 
retained, whilst in both cases tannin is necessarily precipitated. 
The presence of salts in tanning extracts is much to be depre- 
cated, since they accumulate in the tan pits to the detriment of 
the leather. 

Roy has shown that the so-called decolorizing processes are 
beneficial to the extract, not because they eliminate coloring 
matters, for they do this in- a very minor degree, the color of 
the liquor after treatment being but slightly diminished if esti- 
mated on the basis of equality of tannin content — but because 
they precipitate, together with the first portions of tannin, 
certain earthy and metallic bases, such as lime, magnesia, 
manganese, iron and copper, derived from the wood and from 
the apparatus. It is these foreign matters which are taken up, 
combined with tannin, by the leather, imparting bad color and 
harsh and brittle grain. By substituting an aqueous solution 
of potassium ferrocyanide for the precipitate previously used, 
Roy has succeeded in removing these metallic compounds 
without appreciably decolorizing the extract, and finds that 
the leather produced by the treated extract is in every way 
comparable with that prepared with oak bark liquor made in 
the tan-yard. 

It follows that tanning extracts must be examined for salts 
of the alkalies and alkaline earths, and for metallic compounds, 
and valued in accordance with their content of these, as well 
as with their content of tannin. 



CHAPTER VI. 

SOAKING AND SOFTENING. 

WHERE it is possible to do so, the hides should be carried 
through whole until the tanning process is completed and then 
cut into sides. 

The hides should not be soaked in putrid soaks, as valuable 
gelatine is thereby destroyed — fresh water being cheap. 

A German tanner, speaking of soaking, says that good econ- 
omical practice requires great care to be taken in soaking 
hides. He uses principally cow-hides averaging 60 to 70 
pounds in weight, and they reach him salted. He says that 
his first work is to free these hides from dirt and salt. Econ- 
omic methods require that the hide should not be handled 
oftener than is absolutely necessary, and this can only be 
avoided by systematic arrangements as to the progress of the 
various stages. Soaking hides in wheels with a constant in and 
out flow of water is one of these methods which is supposed to 
soften and cleanse the hide. It does it, but alas, too much so ! 
The salt has so acted on the hide that its most valuable con- 
stituents, which are very soluble, are easily washed out, espec- 
ially from the thinner portions of the hide, which will show 
with a heavy loss in the finished leather. The same danger is 
incurred in soaking hides in the common tumbling barrel, 
drum or wheel. Better results are obtained from a wheel di- 
vided^nto four compartments. The falling and heavy beating 
of the hide from one side of the wheel to the other is thus pre- 
vented, and the movements are more gentle and of a rolling 
nature. The simplest and best method is soaking in a water 
pit or box. He prefers a number of such pits, made of 
masonry and cemented, arranged in a row. Three or four of 

(78) 



SOAKING AND SOFTENING. 79 

such will be enough for an ordinary tannery. They should be 
arranged with a waste pipe to empty them, and large enough 
to hang the hides in their full length. The hides can then be 
transferred from one pit to another. Two days' soaking, with 
four changes of water, is sufficient to cleanse the hides thor- 
oughly. Hanging the hides is better than throwing them in, 
as it saves labor, and gives them a more even soaking. The 
best plan is to hang the hides on sticks the length of the back 
bone, low enough to be covered by the water, draw the plug 
every twenty- four hours, rinse off salt and sediment and run in 
fresh water. 

Green or native slaughtered hides cannot be too soon put 
into work, for it is true that as soon as life ceases decomposi- 
tion commences, except a detergent be applied. Salt is very 
generally used for this purpose, and is effective, although not 
the least injurious agent that might be used. Some have a 
great aversion to salt, but it is one of the easiest evils to remove. 
Borax is a better agent than salt for preserving hides and 
skins, and is very easily removed by soaking. 

Dried hides and skins are too various to particularize, and 
require a variation in soaking, depilating and cleansing from 
the depilator before tanning is commenced, if a good return is 
expected. Green hides and skins should first be well cleansed 
from dung, dirt and any extraneous blood there may be re- 
maining on them, and then well soaked from two to six hours, 
according to the kind of skin or hide. 

The preparation of hides and skins should commence by first 
cleansing them from dirt, salt and blood previous to using any 
depilatory process — more especially from blood or albumen, as 
they deteriorate all kinds of leather where any portion is left in, 
and prevent a full expansion of the fibrine, which should be 
fully extended and clean, that the tannic acid may have free 
access to and form the chemical combination with it ; salt also 
should be thoroughly eradicated ; then we have the hide or skin 
free to operate on for depilation. What are called green or native 
hides and skins are very frequently saturated with salt to pre- 



SO THE MANUFACTURE OF LEATHER. 

serve them in transit to the market, or to keep them from week 
to week, and are often stored by the tanner previous to putting 
into work. These are generally subjected to a washing in pits. 
This we would call a partial cleansing, but not an eradication 
of either salt or blood, although a gradual decomposing of the 
pelt, and the first step toward reducing the quality, weight and 
profit. 

Foreign salted hides and skins are subjected to the same 
kind of treatment, but for a longer space of time, and from the 
lengthened time they have been in salt, which has extracted 
much of the water of the pelt, it does not act so quickly ; yet 
before it is considered fit for lime, or other depilator, the same 
waste commences as in home slaughtered hides treated by this 
mode. 

Dry salted hides, kips, etc., require a longer time to get 
them into a state fit for the depilatory process. These are 
generally put into a pit of water kept for the purpose, called a 
soak, and used from time to time until it becomes quite putrid. 
The staler it is the more effectively it softens the pelt, but often 
it is found that the flanks and thinner parts are damaged or de- 
composed before the stout parts or shanks and heads are 
rendered as soft as the pelt should be in a natural state, and 
must be made before liming, etc. 

Dried hides and skins are still more difficult to bring back 
to the state they were in when taken off the animal, because of 
the carelessness in drying before they are stored or packed. 
There is much uncertainty about the soundness of every part 
of the hide. Defects do not show themselves till put into 
work ; then every part that has not been perfectly dry or has 
been tainted before drying, will appear either by the hair com- 
ing off, the grain peeling,. or often large portions of the hide 
rotting away. Even when the hides are perfect, the soft and 
thin parts are damaged by decomposition before the thick, 
hard parts are nearly soaked, although stocks or tumblers are 
used to facilitate the softening ; yet three or four weeks are 
often occupied in this preparation by the general mode, the 



SOAKING AND SOFTENING. 8 1 

uncertainty of which causes this class of hides to be much 
neglected by our tanners, though they should be the most 
remunerative in our trade, the leather produced from them 
meeting with ready sale. Various modes for improving the 
preparation of this class of hides have been brought forward, 
and some experiments have been made, but there has not been 
much progress in this direction. 

Dry foreign hides and skins have long been neglected by 
tanners on account of the difficulty of bringing them back to 
the soft state they were in when taken off the animal, and the 
uncertainty of getting the whole of the pelt into a state that 
will make leather. This arises from two causes — first, from 
the hides being imperfectly dried, for when any moisture is left 
in, before packing for transit or storing, although it may not be 
observable to the eye of the purchaser, they will rot in the 
soak, and be worse when put into lime or other depilator. 
Another very general cause is that, with present modes of 
softening by stale foul soaks, the thinner parts are deteriorated 
before the stout parts are softened. 

The tanner has no control over the first cause and cannot 
guard against it except by buying at a price that will allow for 
these defects ; but the latter cause may be avoided if a suitable 
soaking liquor is used. This has been accomplished by the 
aid of chemistry, and results prove that the foul soak may be 
dispensed with, not only without loss, but with increased profit. 
The coarse buffalo will yield to this chemical soak, and the hard 
dry calf will be made fit for glove kid. 

While speaking of this important part of preparing the hide 
or skin we would draw attention to the necessity of its being 
done thoroughly. Too much care cannot be taken at this 
stage, for if the pelt is not fully developed it cannot be rem- 
edied afterward. Such a soak should be used that no danger 
is to be feared from leaving in till every part is fit for the de- 
pilatory process, yet the weaker parts not injured. Stocks, 
drums and tumblers are a great acquisition, but chemical aid 
united to mechanical skill crowns the whole. 
6 



82 THE MANUFACTURE OF LEATHER. 

The usual mode of softening dry hides for sole leather by- 
putting them in stale old soaks is very offensive, and very pre- 
judicial to the pelt, as most tanners know to their cost. Some 
lessen the risk by putting them through stocks or tumblers ; 
but many tanners still do without the aid of machinery in this 
part of the preparation, forgetting that the longer the hide is 
in a foul soak, the less weight of leather will be realized, 
through the weaker parts exuding their gelatine. This is one 
of the causes of old soaks being so offensive, as every addition 
decomposes and increases the nuisance. 

We would recommend a chemical soak that might be used 
with or without the aid of machinery, although stocks or tum- 
blers are a great acquisition, not only in the saving of time, but 
in preventing loss, for the more quickly a hide is softened the 
less is drained out of it. The time for various kinds will differ, 
but from our own observation we should say East India kips 
put into clean water over night may be softened by aid of ma- 
chinery in three hours the next morning, or without mechani- 
cal aid, in two days or less, dry calf in proportionate time. Dry 
buffaloes, soaked in the same way twenty-four hours', we have 
seen well softened with six hours' tumbling ; still, we would not 
place too much value upon speed alone. We should remem- 
ber it is quality and weight that is the desideratum, and judg- 
ment must be used to get the hide back as near to its natural 
state as possible before it touches any depilatory composition 
or liquor, which roughly we would say may be done, from calf- 
skin to buffalo or dry flint hide, in from six hours to three days. 
Dry salted skins will soak more regularly than skins that are 
simply dried, but these, where machinery is not used, should 
be well worked over the fleshing beam daily until they are in 
good condition. Plain dried skins should always be worked 
over the beam after the first few hours' soaking, for there are 
many folds about the edges that even with machinery will not 
open so as to soften properly unless this is done, and the same 
may be profitably practiced with green home-slaughtered hides 
and skins, for where they are dry at shanks from exposure in 



SOAKING AND SOFTENING. 83 

transit, the depilator will injure and not act properly. These 
also may be advantageously put into a chemical soak for a few- 
hours, to prepare them for the depilating liquor or compound. 

All hides and skins, if not bruised by tumblers or stocks, 
should be well worked over the fleshing beam till the loose 
flesh is thoroughly softened and pulpy. If this is not done it 
is impossible for the pelt to progress satisfactorily. Some say 
the nerve must be broken, but it is sufficient if the veins and 
membranes are so softened that they rise from the true skin. 
They will then allow the liquors to pass through the flesh to 
be easily removed after unhairing. 

Borax, as is well known, is largely used in laundries for 
softening the water, and by packers for preserving meats. It 
must, therefore, prove an invaluable agent to tanners. To 
soften 1,000 gallons of water, five pounds of borax are used. 
It is dissolved in boiling water, poured into the vat or tank 
under vigorous stirring. Borax is one of the gentlest of the 
alkalies, and is one of the most perfect of the cleansers. It 
is equally applicable to all kinds of leather, and it will pay all 
leather manufacturers to use it in their soaks. The Pacific 
Coast Borax Co., New York, Chicago and San Francisco, are 
the largest producers of it in this country. 

Borax and alum in combination will soften very hard water, 
by removing all the mineral matter and impurities, leaves the 
water pure and soft. Nearly all other chemicals and compounds 
used for the purification and softening of water leave traces of 
their presence behind, which very often give more trouble than 
the primary cause which it was sought to remove. 

By using pure water in the soaks the use of destructive 
chemicals is not only minimized but the very best results are 
obtained at much less cost than where impure water is em- 
ployed. At a cost of seven cents for borax and alum, one 
thousand gallons of water can be purified and made soft. 

Most natural waters, as is well known, contain small quanti- 
ties of alkaline salts and earth. In using such waters for swell- 
ing, cleansing and washing the hides, the swelling influence 



84 THE MANUFACTURE OF LEATHER. 

which these salts have upon the cori'in must be taken into 
consideration. 

In hard water containing much of these salts the skins must 
remain for a shorter time than in soft water, that is, such as 
contains but a small quantity of salts or none whatever. 

Soaking calf-kid and light hides depends on the weather. 
Ten hours will be enough if the chill is off the water. Steam 
can be used in winter time, but with judgment. 

SOFTENING. 

It is usual to soften dry hides and skins in the hide-mill 
after they come from the soaks and have been divided into 
" sides," and previous to subjecting them to the liming process, 
and the time which they are worked in this mill depends upon 
the hardness or softness of the hides or skins. For the sides 
that are intended to be worked for upper leather, the usual 
time is from one-quarter to three-quarters of an hour, while 
skins that are intended for the production of morocco and kid 
leathers are usually worked from ten to twenty minutes. 

The construction of hide-mills differs greatly for the various 
branches of leather manufacture. Those employed for soften- 
ing hides and kips are similar to the fulling mills common in 
woolen factories ; while the mills used for manipulating skins, 
such as goat and sheep skins intended for the production of 
morocco and kid leathers, are sometimes in the form of a large 
revolving drum, the interior of which has a number of oak pins 
attached securely to it, and so arranged as to soften the skins 
as they fall upon them, or in other ways continually come in 
contact with the pins. The number of skins placed in a mill 
of this kind at one time is from one hundred and fifty to two 
hundred, and the morocco and kid tanners where it is used, 
call it a "pin-mill." 

The morocco and kid tanners of Philadelphia, Penna., employ, 
sometimes, a softening mill for the dry skins of a very different 
construction, which consists of a central, vertical, or upright 
shaft, on the top of which is keyed a beveled-wheel, which 



SOAKING AND SOFTENING. 85 

meshes with a suitable pinion. About two feet above the 
socket in which the upright shaft revolves, and passing through 
and secured firmly to the main shaft, is a second shaft about 
fourteen feet long, and extending horizontally at right angles 
with the upright shaft so as to divide itself into two arms of 
equal length. About one foot from the end of each of these 
arms there is an iron collar secured to the shaft, and against 
each of these collars a large granite roller, about four feet in 
diameter and eight inches face, is rested, the ends of the pro- 
jecting arms of the horizontal shaft passing through the centre 
of the stone rollers, which are held in place by large iron 
washers which play loosely on the shaft against a steel pin. 

A pit is excavated about three feet deep, following the circle 
described by the inside vertical face of the two stone rollers. 

The socket in which the main or upright shaft revolves is 
placed on a level with the bottom of the stone rollers, and is 
supported upon a pedestal firmly planted in the centre of this 
circular pit. 

A workman stands in this pit and arranges the skins under 
the rollers as they revolve, sometimes exposing the flesh side 
and at other times the hair side to the rollers, and all the while 
keeping them moistened by throwing water upon them, which 
he obtains from the bottom of the pit in which he is standing. 

Mills of this kind may have their advantages for softening 
skins, or they would not be employed by some of the largest 
morocco and kid tanners in this country ; but they are in our 
opinion both clumsy and dangerous, as it is simply a question of 
time when one or both hands or arms of the workman who 
attends them will be crushed by the rapidly revolving stone 
rollers, and besides the skins are constantly exposed to injury 
by remaining too long in one position under the rollers. 



CHAPTER VII. 



DEPILATION OR " UNHAIRING. 



LIME. 



A DEPILATORY is any substance which has the property of 
removing hair from hides or skins without injuring the texture. 

Some skins with which the tanner has to deal are depilous, 
that is, without hair, such as alligator skins and skins of ani- 
mals of the lizard family, which are quadruped, corticated and 
depilous — that is, without wool, fur or hair. 

In leather manufacture hides and skins are steeped in a solu- 
tion of lime in order not only to remove the hair, but at the 
same time to swell the hide or skin ready for the reception of 
the tanning liquor. 

There are many methods for accomplishing the depilation or 
unhairing of hides and skins, but it is commonly achieved by 
placing them in a solution of lime until the hair bulb is loosened, 
thereby allowing the hair to be readily rubbed or scraped off. 

Lime is an alkaline earth of great economic importance. It 
is the oxide of the metallic base calcium, but neither this metal 
nor its oxide occurs in nature in the uncombined condition, 
although existing in enormous quantity in various combina- 
tions. Lime, as artificially made for use in the arts, is prepared 
by calcining limestone or marble, or seashells, in properly con- 
structed furnaces, known generally as lime kilns or simply kilns. 
By this process the carbonic acid is driven off from the lime, 
and the latter remains as an infusible amorphous substance, 
which is white when pure limestone has been employed. In 
this condition it is commonly known as quicklime. When ex- 
posed to the air it attracts moisture and falls into powder with 
greater or less rapidity, according to the humidity of the atmos- 

(86) 



DEPILATION OR " UNHAIRING." 87 

phere and the quality of the lime. This process is called air- 
slaking. Lime for tanners' use is slaked by the addition of 
a large quantity of water, which is absorbed with avidity and 
with considerable evolution of heat. 

There are few limestones which do not contain a greater or 
less quantity of sand and clay, or of silicates of various bases 
mixed with the calcareous material. 

The lime as prepared from various qualities of rocks varies 
in character with the nature and amount of this foreign admix- 
ture. Limestone containing less than 5 or 6 per cent, of im- 
purities yields a rich or, as it is often called, a fat lime. With 
more than that amount the lime is poor, and does not augment 
in bulk to any considerable extent when slaked with water. 
The rich or fat lime is the one which is of the most importance 
in tanning. 

The use of lime is often inconvenient and in many ways un- 
satisfactory, as owing to the energetic action which free lime 
exerts on animal tissues, a considerable portion of the gelatin- 
ous tissue of the hide is disintegrated and decomposed during 
the liming process, and removed from the hide in the form of 
soluble gelatine, or else so altered as to be rendered incapable 
of combining with tannin, thereby incurring a serious loss in 
the weight of leather that should be produced, and in its qual- 
ity, as the skins or hides treated by this process produce 
leather less supple and more brittle than is desirable. 

These objectionable results are more of a physical than of a 
chemical character; the principal modifications of the chemi- 
cal constitution of the hide or skin treated by the lime process 
are the slight increase in the quantity of lime which it originally 
contained, and a decrease in the quantity of fatty matters due 
to the saponification caused by the lime ; the harshness and 
brittleness imparted to the leather being caused not only by the 
saponification of the fatty matters, but much more so through 
the presence of the quantity of lime which penetrates into the 
tissues. 

Suppleness being an indispensable requisite for upper, mo- 




88 THE MANUFACTURE OF LEATHER. 

rocco, and other kinds of leather, it is restored to them after 
being treated by the lime process by subjecting them to the 
action of a bating process, performed by immersing the hides 
or skins in a solution of hen, pigeon or dog manure, bran, coal 
tar bate, and various other solutions, the object of such treat- 
ment being to neutralize the lime contained in the tissues. 

This "bating" is usually performed in consequence of the 
employment of lime for depilating, and as both of these pro- 
cesses are expensive and add largely to the cost of producing 
all classes of pliable leather, it is much to be desired that some 
substitute for lime should be found which would be generally 
acceptable to tanners, and obviate the bating process as well 
as lessen the expense of unhairing hides and skins. 

From the large amount of attention that is being given to the 
subject of depilating, both in this country and in Europe, and 
from the tendency of the age to cheapen all the manufactured 
products of general consumption, we are probably safe in say- 
ing that the time is now near at hand when the slow, inconven- 
ient process of depilating by lime must be succeeded by more 
effective, rapid and economical methods. 

Some of the inconveniences of the liming process we recapit- 
ulate as follows : 

i. The contact of caustic lime alters, more or less, the texture 
of the hide, and permitting it to penetrate the pores, it remains 
in them in the state of caustic lime, carbonate, or lime soap. 

2. The rinsings in water, bating, and the workings remove it 
only partially, leaving an impediment to thorough tanning. 

3. It also hinders the ready penetration of the tan liquor, and 
the perfect combination of tannin with the skin, and so obsti- 
nately resists removal during all manipulations that a portion is 
always found in the best leather. 

These disadvantages have already led to numerous efforts for 
the substitution of other agents, which we shall enumerate later on. 

The present process to which hides are subjected is termed 
"raising," and by it the pores are distended, the fibres swollen, 
and the hair loosened. These results are effected by means of 



DEPILATION OR "UNHAIRING." 89 

alkaline or acid solutions, and by sweating or fermentation. 
Milk of lime, as we have stated, is the alkaline liquor generally 
employed. Lime water has been proposed as a substitute, but 
it is less permanent in its action, and requires frequent renewal 
in order to insure the perfect cleansing of hides. 

The primitive manner of removing the hair was to shave it 
off, but lime was employed even by the early Egyptians. The 
depilating process, in addition to swelling the hide, thereby 
loosening the hair and disposing it to yield readily to the de- 
pilatory operation, also facilitates, by opening the pores, the 
absorption of the tannin. 

If there be a desire to tan quickly, and produce good and 
heavy leather, it is highly important that the hides or skins 
should be properly prepared in the beam house. As the after 
results depend largely upon the intelligent care bestowed here, 
much more attention should in practice be given than most 
tanners are inclined to grant. 

All hides that are intended for limed stock should be put in 
the right condition for the lime — that is, soft enough, but not 
flaccid, as dried skins may be greatly injured by being softened 
too much. A hide fresh from the animal is the best criterion 
as to the condition, for in that state it is best suited for the lime. 

When placed in the lime they should be frequently handled 
or agitated, and should remain in the solution no longer than 
may be necessary to loosen the hair in order that it may be 
readily removed. 

The ancients and those whom progress has failed to reach, 
said and the latter say still, "Who limes, tans." Any tanner 
who entertains such ideas tans his stock without a thought of 
the difficulties he is creating for the currier. 

Lime is a factor at the same time useful and hurtful, and it 
therefore becomes necessary that the tanner should occupy 
himself actively with the conduct and the good management of 
his lime pits, and he should in case of necessity entrust this 
work only to a reliable man, a good workman. 

Most tanners neglect their work at the lime pits, and when 



90 THE MANUFACTURE OF LEATHER. 

our American calfskin tanners fully realize this point, take care 
of their lime pits, and see to the intelligent beam work of their 
stock, they will produce calfskins of the first quality, for we 
possess better bark for this work than can be found in Nor- 
mandy or any portion of France. 

We shall diverge for a moment and speak of the proper treat- 
ment of calfskins in the limes. When the slaughtered calfskins 
peel they should be immediately taken out of the lime. After 
having allowed them to drip well, put them in a vat with enough 
water to cover them without floating. They thus undergo a 
first disgorging. They may, if necessary, remain in this water 
for eight or ten days without spoiling. This method is prefer- 
able to piling, for while in the water the skins disgorge and the 
action of the lime is weakened, while in the pile the lime con- 
tinues its action, and if workmen in piling are not careful to 
open them evenly the skins get what the curriers call " lime 
folds," which are almost impossible to eradicate in currying. 
But best of all, as soon as the skins peel take them out of the 
lime pits, rinse them and unhair them at once, as promptness 
in the execution of labor is an economy of capital. From this 
first stage the work must go on as fast as possible. 

Salted calfskins, after being properly soaked, should be put 
into the dead lime pit, and afterward treated the same as 
slaughtered stock from this point ; but the dry skins require a 
milder lime liquor than the salted skins and the fresh slaugh- 
tered stock. This work is thus rendered a little slower on 
account of the lime liquor in the dead lime pit having been 
previously carefully weakened. 

Lime in depilating has been at times replaced by acid liquors, 
but their employment requires the exercise of judgment. The 
dilute mineral acids make the hair yield easily, but at the same 
time they swell and soften the hide too much, so that the use 
of organic acids is preferable. In some tanneries lime is re- 
placed by a mixture of slacked lime and ashes. Through the 
mutual action of the lime and the carbonate of potassium a 
caustic alkali is formed, which operates more energetically. 



DEPILATION OR " UNHAIRING. 9 1 

Lime vats are constructed either of timber or of masonry, 
and in tanneries where hides are worked they are sunk into the 
ground so that the tops of the vats are on a level with the floor 
of the beam-house, but in goat and sheep skin tanneries the 
vats are partly below and partly above the level of the floor. 

The vats destined to swell the hides to facilitate the depila- 
tion and raising are usually constructed so as to take sides in- 
stead of whole hides, the hides being usually split after soaking, 
which answers for upper leather ; but it is very much better for 
the stock that is intended for sole, belt and harness leather, to 
lime the whole hides, and then if they are not carried through 
all the processes of tanning to split them into sides after the 
liming. 

When split previous to liming, the thin portions of the hide, 
shoulders, etc., contract to a much greater degree than the 
butts and other thicker portions, and consequently the back 
line is irregular, which would not be so noticeable if the lime 
had uniform action on the whole hide, thus economizing the 
waste in cutting sole and harness leather, but more especially 
belt leather, where straight back lines are very desirable. 

The number of hides determines ordinarily the quantity of 
lime necessary for each vat. To make a new vat, throw into 
into it unslacked lump lime, cover with water gradually so as 
not to drown it, and stir well with a stirrer until slacked and 
reduced to the consistence of milk. This operation completed, 
leave it until it is ready to receive the hides. Usually the lime 
is prepared in a hogshead, and from this poured into the vat, 
care being observed to retain the sediment in the bottom of the 
hogshead, which keeps the lime vats cleaner and is beneficial 
in many respects. The vats are distinguished as dead, weak 
and live vats, and sometimes as old and fresh limes. The dead 
or old vat is that which has been frequently used and which 
has been nearly exhausted of its strength ; the weak is that 
which has been used long enough to deprive it of a portion of 
its force, and the live or fresh vat is that which has not yet 
been worked. 



92 THE MANUFACTURE OF LEATHER. 

It is easy to understand that the live vat becomes success- 
ively the weak and the dead vat. When a tanner uses more 
than three vats he establishes between the dead and the live 
vats as many middling term vats as convenient, and the whole 
of the vats are called the raising series. 

The raising should be commenced in the dead vat, and con- 
tinue in consecutive order through the series to the live vat. 
In some tanneries in Europe the series consists of twelve or 
more vats, and in that case there should be a graduation in the 
strength of the liquors. The duration of this operation varies 
in different localities, as in all portions of Europe the hides are 
limed for a longer period than with us. 

The practice is still in vogue among some tanners of using 
old limes which are charged with the decomposing matter ex- 
tracted from previous packs, which practice, in warm weather, 
becomes extremely hazardous. 

The time usually employed for liming different classes of 
hides and skins will later on be mentioned in chapters devoted 
to the manufacture of sole, upper, calf, kid and other leathers. 

The power reel is now generally employed for handling sole 
leather hides in the lime vats, and it is the most economical, 
convenient and effective method, the sides being strung to- 
gether and passed over the reel from vat to vat. 

American tanners put hides through the soaks and limes in 
about four days. During the last twelve hours of this period 
the packs lie in hot water. The hides are reeled three or four 
times during the first day in limes ; then reeled twice on the 
following day from vat to vat. All kinds of fancy schemes 
have been tried for lessening the destruction of hide substance 
in the beam-house, but tanners still stick to simple handling, 
strong limes, hot water and- short time. By this method 75 to 
80 per cent, of acid hemlock sole leather has been made from 
plump, well-grown, heavy Texas steers, fall kill. This is good 
showing, and it is results that count in this busy world. 

Every intelligent tanner knows that no exact or arbitrary 
rules can be given for liming and handling any kind of hides 



DEPILATION OR " UNHAIRING." 93 

or skins, as the time required varies greatly, being dependent 
on kind and condition of the skins, condition of atmosphere, 
temperature, and temperature of the limes in use, etc. 

In the liming of goat skins it is customary to add about one 
and a half pounds of arsenic to each bushel of lime. 

The " arsenic " used is sulphide of arsenic, and when mixed 
with lime forms sulphide of lime. This acts upon the skin 
vigorously, hastens the unhairing, and is supposed to give the 
skin a finer grain than when lime is used alone. This sulphide 
of lime, however, penetrates to all parts of the skin, and when 
present in excess does not become thoroughly removed in the 
subsequent operations of washing, bating, etc. So an excess of 
arsenic is injurious and would have a tendency to make the 
grain tight and dry so as to cause skins to crack. 

Skins left too long in old limes are apt to have the grain 
somewhat plumped, and the pores very open, as though not 
worked out sufficiently. 

The grain being loose from the flesh is a common occurrence, 
and results from a variety of causes. It indicates that some 
solution into which skins have been placed was too powerful. 

There is no way to tell to a certainty whether or not a skin 
has been sufficiently limed ; only long familiarity with the class 
of skins and their appearance in this state would enable one to 
form a correct judgment. 

Manufacturers of kid are devoting much attention at the 
present to the "cellar" or "beam-house" department of their 
works. These gentlemen, having mastered the new chrome 
process of tanning, are now striving to effect economies and 
improvements in liming and bating. 

Before any real improvements can be made, it is most 
essential to understand just what it is necesssry to accomplish 
by these two important operations, and to recognize the fact 
that rough crude processes which would doubtless give good 
results on sole leather are entirely unsuitable for kid stock 
where the final operation, in finishing, is glazing. Roughly 
speaking, the use of lime is for the purpose of removing the 



94 THE MANUFACTURE OF LEATHER. 

hair, and the operation of bating for the purpose of removing 
lime from the stock preparatory to tanning. If this was all to 
be accomplished, the operations would be comparatively- 
simple, but in the manufacture of glazed stock other important 
results are necessary to success. 

Lime and dog-pure have been used in the beam-house for 
many years ; both are objectionable and have disadvantages, 
yet owing to their long use experience has taught the workmen 
their properties, and they know just about how to deal with 
them in order to attain the desired result. Any other materials 
which could be used in place of these articles would doubtless 
bring new and unlooked for difficulties and would require 
changes in the methods of working in order to make their use 
a success. 

Lime acts upon the roots of the hair ; the hair-sheaths are 
dissolved, thus enabling the hair to be removed on the beam, 
the hair itself being but slightly altered. The effect of lime 
upon the skin itself is most marked, and it is the action of the 
lime other than the removal of the hair, which is most import- 
ant in the preparation of stock for glazed kid. Lime acts 
vigorously upon the true skin ; the fibres swell and absorb 
water, so the skins become plump and swollen and at the same 
time the cement-like substance (coriin), which glues the fibres 
together, is dissolved and the fibres become differentiated into 
finer fibrils and so open up the skin, so to speak, in order that 
it may tan evenly and properly. Another action of the lime is 
upon the natural fat or oil of the skin, converting it into a more 
or less insoluble soap, which is largely removed in the subse- 
quent operations to which the stock is subjected. These re- 
sults therefore are necessary to accomplish by the liming 
operation. 

In the liming of sheepskins consideration should always be 
given to the removal of the grease. This is most economically 
done by a wringer. Some large concerns also use presses for 
this purpose, and some imported sheepskins which have been 
unhaired, fleshed and split, are soaked in naptha. For making 



DEPILATION OR " UNHAIRING." 95 

up a fresh lime for a 4x5x6 feet vat, holding about 900 gallons 
of water, for liming 190 to 200 large sheepskins, there should 
be use five or six pails of stone lime. Strengthen next day with 
three or four pails of stone lime. High liming may kill some 
little grease, but not sufficient to make first-class leather from 
greasy sheepskins. Sulphur and lye in correct proportions will 
not hurt the skin, but we prefer to use commercial sulphide of 
sodium for strengthening the limes. If lye and sulphur be 
mixed in definite proportions they will in time combine and 
form sulphide of sodium. The fresh pulled skins can be entered 
directly into the new lime ; it would be useless to first dilute 
with water, but it will be found that an older lime will make a 
better leather than a new lime. It cannot be told by cutting 
a skin whether or not it has enough lime. Let the limes run 
into the sewer and thoroughly clean vat about every two months. 
Some of the clear liquor from this lime that is run off should 
be used to make up a new lime again. 

What can the disease known as the itch possibly have to do 
with the liming? The itch is a skin disease caused by a para- 
site lodging under the skin of the living animal. We shall see 
in the course of this chapter why we speak of the itch in con- 
junction with liming. It is a fact that a large percentage of all 
skins suitable for glove kids are more or less scabby. This is 
very troublesome because for the delicate shades only such 
skins can be employed as have a perfectly healthy grain, while 
scabby skins, if not too badly disfigured, can be used only for 
very dark colors, sometimes also for white or straw color. If 
the grain is badly disfigured the skins must be finished into 
undressed kid. A further objection to scabby skins is that be- 
sides the disfigurements the quality of the skin has severely 
suffered. In bad cases even an inexperienced buyer will notice 
the trouble, but the more hidden symptoms are difficult to no- 
tice even by experienced men. The extent of this disease may 
be judged from the fact that pretty nearly 50 per cent, of all 
lambskins on Continental markets are scabby. The main diffi- 
culty is found in the fact that although most frequent in the 



96 THE MANUFACTURE OF LEATHER. 

coarser grades, this disease is also quite general among the 
very highest grades of skins. Thus in France the skins of 
suckling goats of unequaled quality, of which a dozen are worth 
$10.00 in the hair, are scabby to the extent of more than 35 
per cent., so that often the front half cannot be used for gloves. 
It requires very experienced skin-buyers in order to get as little 
scabby stock as possible. It seems strange that otherwise 
healthy animals should be affected with this skin disease at 
their birth. This is due to the fact that the disease is inherited 
from generation to generation. This disease manifests itself 
in principally two different forms, the prominent and the 
hidden form. Many tanners, especially lambskin tanners, 
recognize also a third form which they call the " white itch." 
The prominent form is readily recognized even by inexperienced 
eyes, as the scabby spots have often penetrated the entire 
thickness of the skin from the grain to the flesh, or at any rate 
are readily seen, particularly in the flanks, by holding the skin 
against the light. They then appear as dark spots. The 
hidden form is present only under the grain. On the white 
glove kid this form can hardly be noticed, but on colored 
stock it is very prominent. This form of the itch causes all 
colors, especially the delicate shades, to look clouded and dirty. 
Skins in the hair afflicted with this hidden form of disease can 
be picked out only by men of considerable experience by 
means of the general appearance and symptoms of such skins. 
The third form, or white itch, consists of a peculiar disfigure- 
ment of the grain, which latter looks as if it were covered in 
places with granulated sugar. This white itch is not the result 
of any disease, however, but consists of fine crystals of alum 
and salt deposited on the grain. Only recently a lot of skins 
that were thus disfigured, were sent for investigation to Der 
Gerber, of Vienna. They inquired into the details of the man- 
ufacture of this particular lot of skins, and found that the cause 
of this white effloresence, known as white itch, was the result 
of using a deficiency of lime and too much arsenic in the limes. 
This prevented a sufficient loosening of the skin and the result 



DEPILATION OR " UNHAIRING." 97 

was that the alum and salt used for tanning were imperfectly 
absorbed. 

DEPILATING WITH SODIUM SULPHIDE. 

During the past twenty years much has been wrilten and 
many experiments have been conducted with a view to the in- 
troduction of sodium sulphide as a depilatory. At the present 
time, however, it is generally conceded by all progressive tan- 
ners to be an exceedingly useful article in the beam house treat- 
ment of hides and skins. Prof. Eitner, in Germany, Prof. Proc- 
tor, in England, and Prof. Fiebing, in America, have indorsed 
it as a valuable material when properly used, and have recom- 
mended various methods for its application in the unhairing and 
swelling of hides and skins. The consensus of opinion now is 
that to obtain the best results from the use of sodium sulphide 
lime should be used in connection with it. When lime is added 
to a solution of sulphide, the latter unites with the calcium to 
form calcic-sulphydrate and at the same time liberates caustic 
soda, which considerably increases the unhairing and plumping 
effect. A similar reaction takes place when the red arsenic is 
mixed in a solution of lime, a sulphydrate of lime being 
formed, which is the active agent in producing the desired 
effect. The use of arsenic sulphide in this way has been favor- 
ably known to tanners from very early times, but a substitute 
for this expensive and exceedingly poisonous material is found 
in the sodium sulphide, which is much cheaper and just as 
effective. It is now an established fact that the sulphydrate of 
lime does not dissolve out so much of the hide substance as 
when the lime alone is used, and being quicker and more ener- 
getic in its action, both time and space are economized in the 
tannery by its use. 

Prof. Fiebing, in writing upon this subject, says, "that the 
action of lime is throughout solvent and swelling, and more 
actual hide substance is probably lost by pure liming than by 
any other unhairing process. The solvent action of an old and 
fresh lime is nearly the same, while the swelling property de- 
7 



98 THE MANUFACTURE OF LEATHER. 

creases with age. A material that is steadiiy though slowly 
gaining in favor is sulphide of sodium. This substance, though 
not new, is but little understood by the trade. One disadvan- 
tage of lime for unhairing hides intended for any leather where 
a certain degree of solidity and rilling are desired, is its prop- 
erty of dissolving the coriin faster than it will properly loosen 
and distend the fibres. Consequently, if we lime long enough 
to properly prepare the hides for the liquor, considerable loss 
of weight will inevitably follow by reason of the solution of a 
large amount of coriin. If a short liming is resorted to, the 
fibres cannot be properly loosened, and a flat, tinny leather is 
liable to be the result. Now, we have in sulphide of sodium a 
material that will efficiently counteract this undesirable property 
of lime. Sulphide of sodium will loosen and split up the fibres 
much quicker than lime, and if used in proper proportions will 
not dissolve as much coriin as lime. By combinations of these 
two depilatories we can, therefore, obtain an excellent unhair- 
ing agent for almost any kind of leather." 

The method of using the sulphide in connection with lime, 
as recommended by those who have been most successful with 
it, is to dissolve from one-half to three-quarters of a pound to 
each hide, and mix it with about the same weight of lime pre- 
viously slacked. This is thrown in the pit with sufficient water 
to cover the hides and the hides suspended in the solution. By 
this method of suspension the action of the depilatory is much 
more uniform than when the hides are thrown loosely into the 
pit. The length of time required for the unhairing and the 
distending and separating of the fibres will depend upon the 
firmness and flexibility desired in the leather. For sole leather 
from one to two days should be amply sufficient, while for 
upper leather a longer time would be necessary. The same 
kind of mixed depilatory may be used with advantage upon 
calfskins and goatskins, though in this case the skins may be 
agitated and their position changed by the use of a paddle 
wheel attached to the pit, and thereby a uniform action of the 
depilatory be obtained. There are several grades of sulphide 



DEPILATION OR " UNHAIRING." 99 

of sodium now offered in the market, varying in their degree 
of purity. The common salts occur as crystals of a deep- 
greenish-black color, and are contaminated by iron sulphide, 
which produces dark blue stains on the hides and skins. A 
better sort is found in an amber-colored crystal which is com- 
paratively free from iron. The crystals of sodium sulphide 
contain 69 per cent, of water and are very deliquescent, and the 
material should, therefore, be kept in a dry place and from 
exposure to the air. A new and concentrated form of sodium 
sulphide, free from iron and free from water, has recently been 
introduced by the Martin Dennis Chrome Tannage Co., of 
Newark, N. J., who state that it is more than twice as strong as 
the ordinary sulphide crystals and of purer quality. It would 
seem that this form of sulphide should recommend itself to 
tanners, because many of the objections urged against the older 
form of the material are removed. 

The advantages obtained by the use of sodium sulphide may 
be enumerated as follows : 

1. The unhairing and swelling of the hides or skins is ac- 
complished more quickly, thereby saving both time and space 
in the tannery. 

2. The swelling and distending of the fibres is not attended 
by so great a loss of hide substance as when lime alone is used, 
thereby insuring plump and full leather with a minimum loss 
of weight. 

3. The hair and epidermis are so thoroughly loosened that 
the unhairing operation may be conducted in a wash wheel, 
thus saving the labor of beam work. 

4. The'sulphydrates being more soluble than pure lime, it 
follows that the depilating material can be removed from the 
hides or skins easily, quickly and inexpensively by mere wash- 
ing with water. In fact, it is claimed by some that if the wash 
water is used warm, about 8o° to 90 F., no bating will be re- 
quired, especially in case the hides are intended for sole 
leather. 

Upon these and many other considerations it seems safe to 



IOO THE MANUFACTURE OF LEATHER. 

predict that sodium sulphide will be more and more favorably- 
recognized by tanners as a valuable and almost indispensable 
material in the art of leather manufacture, and that the future 
will bring it into much more general use than at present. 

This material is also very largely used for wool pulling. 

Sodium sulphide is a crystallized chemical substance of 
definite and regular composition. Any competent chemist can 
determine its strength. Its value as a depilatory depends solely 
upon the amount of monosulphide of sodium which it contains, 
and not upon any patent or so-called improvement whatever. 
One hundred pounds of crystal sulphide of sodium contain be- 
tween thirty-one and thirty- three pounds (31 and 33 percent.) 
monosulphide of sodium. For the convenience of consumers 
the dealers in sulphide of sodium guarantee this product to 
contain at least 31 per cent, of monosulphide of sodium, and 
if desired, will furnish a chemist's certificate to that effect. 

Ordinary sulphide of sodium is frequently sold under a fancy 
name at a higher price than it is worth. 

Tanners are also offered a so-called "improved" sulphide of 
sodium, wherein the " improvement " consists in adulterating, 
or weakening, or cheapening it with common sulphate of soda, 
an article worth on the market less than half a cent a pound. 

Both of these are impositions. Fortunately they can be 
easily detected. 

The late John W. Stevens says of the sulphide of sodium 
process : 

"Tanners who are making specialty of imitation goat, book- 
binding or pocketbook leather, wherein the leather is split 
down to a very light substance, should not go too extensively 
into this process until after several experiments have been 
made with the sodium, and then by using it in a mild form, for 
the following reasons: By the use of sulphide of sodium a 
thicker grain is produced than by the use of lime and hen 
manure, and when split down to a very light substance the 
grain becomes tender. Again, leather suited for imitation goat 
finish must have a thin grain to produce the desired character 



DEPILATION OR " UNHATRING." IOI 

and prominence in the print. When too thin, it would be 
found difficult to throw up a figure in the cork boarding to re- 
semble the real goat skins. In all other respects the quality of 
the leather is superior, being of a tougher fibre, finer flanks 
and of a supple and elastic nature, so desirable for fine shoe 
leather. 

" For boot and shoe oil grains, glove grain and imitation 
calf, where the grain is buffed off in finishing, the sulphide of 
sodium process is especially adapted, as also for slaughter sole, 
oak and union crops and backs, which are also submitted to 
the buffing operation to produce a uniform finish and light 
color to the soles when made into shoes. This process will 
also be of great value to tanners making sole and upper leather 
from dry flint hides. There will always be found in this class of 
hides many that are sunburnt, particularly those coming from 
Africa and South America, and it is a difficult matter to work 
them in warm weather. To soak them sufficiently long to 
bring the hide back to its original condition, putrefaction would 
set in, and unless the hides are made pliable before going into 
the lime, all subsequent labor is lost in the endeavor to produce 
plump and heavy leather. For a soak of fifty whole hides in- 
tended for upper leather, and averaging some twenty pounds 
eaeh, dissolve one pound of the sulphide of sodium in hot 
water and pour into the pit, previously filled with cold water : 
mix thoroughly with plunger and throw in the hides. This has 
a tendency to not only preserve the hides during the soaking, 
but will soften up the sunburned portions and greatly facilitate 
the unhairing process at a later stage. After being immersed 
two or three days, pull up the hides and examine their condi- 
tion. Those that have yielded more readily to the water and 
sodium throw aside, and carry them along by first milling in 
the wash-wheel without water until a friction is created and the 
former rigid feeling broken ; then let into the wheel a bounteous 
supply of water until the hides are practically freed from blood, 
dirt and manure, when they will be in good condition for flesh- 
ing. The balance of the pack, should the hides show no sign 



102 THE MANUFACTURE OF LEATHER. 

of putrefaction, may be thrown back into the soak again after 
lying in pile a few hours to partially sweat them, when they will 
soften more readily in the solution. It will not be necessary to 
run off this solution, but fill the pit again with clear water until 
the entire pack is soaked. If in cold weather, and the water is 
cold, the same may be used with some replenishing of water and 
the sodium for several successive packs, as the ammonia, blood 
and filth accumulated will facilitate the soaking of dry flint 
hides ; but care must be taken that this may not be carried too 
far, and that the hides be pulled out frequently, and then select 
out such as yield more readily. For sole hides of greater aver- 
age weight, add one-third to one-half more of the sodium in the 
soaks, and treat in the same way, being careful not to use such 
a quantity as will loosen the hair too freely while in the soaking 
process, else a loss of weight would ensue when the hides are 
later on immersed in the sodium and lime solution for completely 
removing the hair. For soaking dry kips and calf-skins, a com- 
paratively small amount of sodium per skin would be required, 
and may be regulated by the average weights, although skins 
of finer texture require a stronger solution to effect the desired 
object than do heavy, coarse hides." 

The use of sulphide of sodium as a depilating agent is very 
simple. A definite quantity being weighed off, it is dissolved 
in a certain amount of warm water. After some stirring the 
solution is perfected. It is of brown color and clear. It will 
not deposit on standing, and, therefore, need not be stirred be- 
fore use. The solution will not ferment, and can therefore be 
kept for an unlimited length of time. The density of this solu- 
tion is of no importance ; but it is advisable to take twenty 
quarts of water for every pound of sulphide of sodium. Ac- 
cording to the amount of hide worked in per day we must make 
up a larger or smaller quantity of the solution. The solution 
can be made up in a cask or barrel. It is imperative to know 
the concentration of this solution, i. e., we must know how 
much sulphide of sodium is contained in every quart or gallon 
of the solution. We recommend a concentration of one pound 



DEPILATION OR " UNHAIRING. IO3 

of sulphide of sodium for twenty quarts of water. If we add to 
a lime, say, three pounds of sulphide of sodium, which quantity 
is about sufficient for an ordinary lime holding about 800 to 
1,000 lambskins, according to size of the skins, we must take 
sixty quarts of above solution. It is not rational to add this 
entire quantity at once to the lime, but it should rather be 
given in three or four portions, adding a portion every other 
day. For every portion of sulphide of sodium solution given 
we should add one bucket of slacked lime. The slacked lime is 
dissolved by stirring with cold water, and the requisite quantity 
of sulphide of sodium is added thereto. This mixture is then 
added to the limes, and the latter thoroughly plunged. In 
making up a fresh lime no sulphide of sodium is added at first, 
in order to give the skins a chance to plump. After the first 
hauling of the skins the fresh lime is strengthened with above 
mixture of slacked lime and sulphide of sodium, and this mix- 
ture is added for each subsequent strengthening. As regards 
the relative proportion of sulphide of sodium necessary to ac- 
complish the same work as arsenic, the quantities of both ma- 
terials are identical, i. e., one pound of sulphide of sodium will 
do the same work as one pound of arsenic, and vice versa. 

For an ordinary lime containing about 800 to 1 ,000 lambskins 
(according to size), we, therefore, need three pounds of arsenic 
or else three pounds of sulphide of sodium. The solution of the 
arsenic can be accomplished by mixing some with lime at the 
time of slacking and thoroughly stirring. This arsenic-lime 
paste can also be kept for a long time without spoiling, and 
can, therefore, be made up in a sufficient quantity to last for a 
month or so. Of course, the quantity of arsenic contained in 
a quart or a gallon of the paste must be carefully noted. An- 
other way of dissolving the arsenic is by vigorously stirring it 
with milk of lime for about half an hour or until the brown 
color of the mixture has acquired a steel-gray coloration. This 
mixture is then mixed with milk of lime previously diluted with 
hot water. The hot water materially aids the solution of the 
arsenic. The first method of solution is, however, preferable. 



104 THE MANUFACTURE OF LEATHER. 

The most striking effect of sulphide of sodium in the limes 
is its property of bringing back the grain to its fresh, green 
state, even if the skins or hides have become withered by 
reason of long storage. No other depilatory agent brings 
about this effect — even arsenic-lime will not restore to the 
grain its natural green freshness. What we mean by speaking 
of a withered state of the grain is probably not clear to the 
majority of tanners. To be sure they have noticed that some- 
times the grain of the skins appears clouded, while at other 
times it is clear after unhairing ; but they have never investi- 
gated the cause of this fact. Now, the best way to understand 
just what we mean is to make the following experiment : Take 
three skins as near alike as possible and unhair one in the or- 
dinary lime, the next in a lime strengthened with arsenic, and 
the third with sulphide of sodium. Unhair at the same time 
and spread out alongside of each other, and note the wonder- 
ful difference in the appearance of the grain. The one limed 
with pure lime, particularly if the limes are not fresh, will show 
a yellowish-gray, clouded grain ; the grain of the skin limed in 
the combination of arsenic and lime will appear clouded and of 
bluish-gray color, being more pronounced the older the limes; 
while the last skin, unhaired with sulphide of sodium, will 
have a clear, fresh grain, closely resembling in appearance a 
green skin after liming. As we know, those skins that are 
worked in fresh from the slaughter house, are perfectly clear 
and very clean on the grain after liming. 

Now how is this property of sulphide of sodium explained ? 
Let us first note the fact that the longer a skin has been stored 
the more noticeable is the clouded appearance of the grain after 
unhairing, and, vice versa, the fresher a skin is worked in, the 
clearer, fresher and cleaner is the grain. What is the cause of 
this cloudiness? It is due to the substances originally held in 
solution by the blood and lymph of the animal, which have 
gradually dried out on the grain, becoming more insoluble the 
longer the skin is stored, until eventually they have become 
totally insoluble in water. The fact that the impure juices of 



DEPILATION OR " UNHAIRING." IO5 

the blood can be deposited in considerable quantities on the 
grain, can be readily observed on the skins and hides of dis- 
eased animals. Every tanner knows that the criterion of dis- 
eased skins is a remarkable cloudiness of the grain, and that 
this cloudiness can even be diffused throughout the entire skin 
to the flesh side. Sometimes not alone the juices of the blood, 
but the blood itself, can become deposited on the grain. This 
can be clearly seen on the skins of animals which have died 
from disease, which invariably show blood spots, and the flesh 
side of which has a dull appearance. Now that we have found 
the cause of the clouded appearance of the grain to be due to 
the deposited matter of the blood, we must next endeavor to 
discover the means of bringing back this deposited matter to a 
soluble form. For this purpose sulphide of sodium is without 
a rival. The dry blood albumens, etc., are so completely dis- 
solved by sulphide of sodium that the grain, after unhairing 
with this depilatory, is so bright and clean as is otherwise only 
observed in green butcher stock. Another valuable property 
of sulphide of sodium is that it does not dissolve the hide sub- 
stance to any extent if employed at ordinary strength. It can 
be used in quite concentrated solutions without danger, and it 
matters little if the skins are left in longer than necessary. Both 
the hide proper and the grain are usually tough and strong if 
unhaired with sulphide of sodium. Let us sum up the good 
qualities of sulphide of sodium : 

1st. Tough and strong leather, particularly of the grain. 

2d. Closed fibre, well filled leather. 

3d. Bright, glossy grain. 

But sulphide of sodium also possesses some very undesirable 
qualities. We have remarked that sulphide of sodium does not 
dissolve the hide substances to any extent. This property is a 
decided advantage in some classes of leather, but for glove- 
kid it is extremely undesirable. Every tanner knows 
that in order to produce plump, stretchy and good-feeling 
glove-kid, he must remove a certain amount of hide substance 
from the skins by means of the depilatory employed. Now as 



106 THE MANUFACTURE OF LEATHER. 

sulphide of sodium does not possess this solvent property, it 
follows that by its use we cannot achieve satisfactory results for 
glove-kid. Sulphide of sodium plumps the stock similar to 
vitriol. In concentrated solutions it possesses extraordinary 
plumping qualities. The hair bulbs are speedily dissolved. 
In fact we can depilate a dry, unsoaked skin with a very con- 
centrated sulphide of sodium solution inside of a few hours ; 
the skin will swell up to five times its natural thickness, and the 
hair will be loosened sufficiently without dissolving any hide 
substance. If by this process we treat a skin that has pre- 
viously been properly soaked, the same operations will be per- 
formed inside of a few minutes. This fact led tanners to be- 
lieve that sulphide of sodium would be an excellent depilatory 
for glove-kid without the addition of lime, but experiments 
soon showed that something was lacking, and now sulphide of 
sodium is never alone employed for depilating glove-kid or 
alum leather. If sulphide of sodium be employed for any class 
of glove or upper leather, we must always use sufficient lime 
with it to dissolve the necessary amount of hide substance. 
Generally not enough lime is used with sulphide of sodium and 
the result is flat leather; further, the skins are not equalized, 
i. e., that thick skins remain thick and thin skins remain thin. 

It is another undesirable property of sulphide of sodium that 
glove-kid, made from skins depilated with this material, get 
hard and unelastic during the requisite aging. We know by 
experience that alum tawed glove-kid must age a certain 
length of time in order that the tawing materials can properly 
unite with the fibre. We also know by experience the result 
if this aging is not properly done and the leather goes to the 
dyer too fresh. If the skins are colored before having had the 
requisite time of aging, the tawing substance, being only loosely 
held, will be washed out to such an extent as to result in a 
hard, hungry leather. The necessary time required for this 
aging is at least two months, and need never exceed twelve 
months. A naturally mild leather skin requires only a two 
months' aging, while a flat, hard skin necessitates from eleven 



DEPILATION OR "UNHAIRING." IO7 

to twelve months aging before coloring. If sulphide of sodium 
has been employed as a depilatory we must shorten the time 
of this aging to the detriment of the leather, for above mentioned 
reasons. This disagreeable property of leather unhaired with 
sulphide of sodium becoming hard during the aging is due to 
the same cause as the flatness of this leather. A green skin is 
flat and unelastic as compared to well-tanned leather. Why? 
The naturally loose fibrous network is pasted together, so to 
say, in its own gelatinous hide substance, which latter has the 
property of getting harder the more the skin dries out. The 
depilating process must remove a certain amount of this gela- 
tinous hide substance, and the spaces so formed must be filled 
by the tawing materials which give to the leather mildness, 
body and good feel. Inasmuch as sulphide of sodium does not 
remove an adequate part of this gelatinous hide substance, it is 
natural that the resulting leather somewhat resembles the green 
skin in its property of getting hard when it dries out completely 
and remaining flat. Another bad property of such leather is 
the difficulty of coloring it, which is also due to the presence of 
too much of the gelatinous hide substance. To sum up, we 
can obtain a good-looking glove kid with sulphide of sodium, 
but it must be quickly sold and at low prices. Manufacturers 
who endeavor to establish a reputation for their goods cannot 
use sulphide of sodium for making glove kid. 

A writer in Der Gerber says : If the practical tanner were 
satisfied to obtain "similar" effects to those produced by arse- 
nic and for some reason wanted to replace the latter by a sub- 
stitute, he would find sulphide of sodium best adapted for the 
purpose. But there is a tremendous difference between "simi- 
lar" effects and identical effects. It is now about twenty years 
ago that the first experiments were made with sulphide of 
sodium in the tannery, and it seemed for a time that a material 
had been found which would entirely replace the poisonous 
arsenic. After numerous and careful experiments had, how- 
ever, been concluded on all classes of hides, from the heaviest 
sole leather down to the most delicate glove kid, it was seen 



I08 THE MANUFACTURE OF LEATHER. 

that although admirably adapted for some purposes, sulphide 
of sodium was not a good substitute for arsenic in all cases. 
These tests brought out the specific properties of both materials, 
and -thus showed us for which grades of leather arsenic and for 
which sulphide of sodium should be used to obtain best results. 
Thus we find that sulphide of sodium is used to this day in the 
manufacture of sole leather and to some extent in the manufac- 
ture of upper leather and morocco leathers, for which classes 
of leather a close fibre and absence of elasticity are required. 
It is a fact that also some glove kid manufacturers still employ 
sulphide of sodium, but these are only those manufacturers who 
strive to turn out large quantities of leather in the shortest pos- 
sible time, irrespective of quality, and who, therefore, sell for 
less than their competitors. For this latter class of manufac- 
turers sulphide of sodium is admirably adapted, as it produces 
a clean grain with a minimum of labor ; it matters little to them 
that the gloves made from their stock often get hard in a com- 
paratively short time. Manufacturers of glove kid who warrant 
their stock to remain soft for a long time cannot employ sul- 
phide of sodium. In former times the only depilatory known 
for all grades of leather was ordinary lime. In the course of 
time qualities were demanded in leather that could not be ob- 
tained by depilating with lime alone. The main requisite de- 
manded of a depilatory in our time is that it should depilate 
evenly and quickly; further, it should thoroughly remove the 
fine hair and cleanse the grain and skin from dirt, and above 
all not plump the hide to that extent peculiar to pure lime. It 
is very important that the time required for liming the hide be 
shortened for many grades of leather, because lime dissolves 
considerable hide substance, and, therefore, pure liming will 
not produce as close and fine a leather as can be made by 
using some other depilatory. Of all the innumerable depila- 
tories "discovered" and "invented" of late, only two have 
come to stay, viz., arsenic and sulphide of sodium. Arsenic 
fulfills all requirements of a depilatory, as above enumerated, if 
mixed with lime. The active depilatory agent of the mixture 



DEPILATION OR " UNHMRING. IO9 

of arsenic and lime consists of several different combinations 
of lime and sulphide of arsenic. Both the sulphide of arsenic 
and the lime have lost their specific properties entirely in 
these combinations. As is the case in all chemical combina- 
tions, arsenic sulphide and lime will combine only in definite 
and fixed proportions. An excess over these proportions of 
arsenic is without any action on the hide or hair, as it is insol- 
uble. An excess of lime, however, will act as such on the hair 
and hide. As in practice, where arsenic is employed in com- 
bination with lime, there is always an excess of lime. We 
really have two different depilatories, viz., a combination of 
arsenic with lime, and pure lime. We have no technical word 
for this combination of sulphide of arsenic with lime, excepting 
the Arabian word "Rusma," or a translation of the German 
and Austrian tanners' word " Gift," designating poison. This 
combination of sulphide of arsenic and lime has some very 
peculiar properties, foremost among these being the property 
of completely eating up the hair in very short time to a pulpy 
mass. This property gives us the explanation of its extraordi- 
nary depilating power. The root of the hair being the soft- 
est part of the hair, this depilatory will naturally first dissolve 
that part, and with this solution the hair will give. The first 
requisite of a depilatory — quick action — is, therefore, fulfilled by 
the sulphide of arsenic and lime combination. Sulphide of so- 
dium in this first effect acts identically with sulphide of arsenic 
and lime. It also eats up the hair in a very short time and 
causes it to give, in the same time as the latter depilatory. Both 
depilatories being so very much alike in this respect, it was 
thought at first that this would also be the case in all other 
respects, and tanners of glove kid were glad to be able to 
abandon the poisonous arsenic. But they soon discovered that 
other properties requisite to a good depilatory for glove kid 
were wanting in sulphide of sodium. Besides the hair proper, 
the animal hide is covered with a short down, similar to what 
is found on the arms and legs of the human body. This down 
is known to the tanners as fine-hair. In the process of unhair- 



HO THE MANUFACTURE OF LEATHER. 

ing a large proportion of these fine-hairs are removed by the 
beamster, providing a proper loosening of these fine-hairs has 
been accomplished by the depilatory. As the coarse bulbs of 
the hair are loosened in shorter time than the bulbs of the fine- 
hair it is often the case that the former give readily on the 
beam, while the latter are still held very firm, and can be re- 
moved only with difficulty or not at all. It is no trick to prop- 
erly loosen the hair proper, but the fine points of depilating 
begin with a proper loosening of fine-hair, and it is here that 
the tanner must be guided by experience and practical tests to 
know when the depilatory has accomplished this result. With 
lime alone the fine-hair may be removed, but pure liming will 
accomplish this only after the soft parts of the grain and hide 
have also been dissolved. To properly remove the fine-hair 
by pure liming without the aid of other depilatories, we would 
have to employ a large excess of lime and also lime consider- 
ably longer. This would not only loosen the hide too much, 
making it spongy, but the grain would be deprived of its gloss 
and toughness by the removal of its most juicy constituents/ 
It is, therefore, necessary to loosen the fine-hair by employing 
some substance in combination with lime that will loosen these 
finer-hairs in a short time and which will not materially attack 
the hide. Such a substance we have in the combination of lime 
and sulphide of arsenic. Without dissolving the soft parts of 
the hide and without disturbing the structure of the hide the 
arsenic-lime acts as a powerful solvent on the bulbs of the hair 
and fine-hair, thus loosening them in a very short time. The 
rapidity of this action is clearly seen by painting the skins with 
a paste of arsenic-lime ; such skins will unhair clean in as many 
hours as it would take days to do the work by liming with pure 
lime. By this painting process, however, we employ the arsenic- 
lime in such concentrated state as would not be possible without 
injury to the hide in the limes. Besides, the object of liming 
is not only to remove the hair, but also to bring about a certain 
loosening of the hide, which latter cannot be accomplished by 
the arsenic-lime, but is done by the lime alone. Considering 



DEP1LATION OR " UNHAIRING. Ill 

that the lime must be allowed a certain length of time to bring- 
about a proper loosening of the hide — eight to twelve days — 
we must correspondingly reduce the amount of arsenic-lime 
which is added to the limes. While we need about nine pounds 
of arsenic together with enough lime to form a paste in unhair- 
ing by the painting process, we take only about two and one- 
half pounds of arsenic for unhairing in the limes for about 1,000 
medium lambskins. These two and one-quarter pounds of 
arsenic are sufficient to bring about a thorough loosening of 
the hair and fine-hair in the limes in about eight to twelve days. 
Of course if we have particularly heavy, dry skins the quantity 
of arsenic may be increased about half, while on very small 
delicate skins the amount should be reduced. We should never 
use much above the requisite quantity of either arsenic or lime, 
i. e., only enough of each to thoroughly do the required work. 
It is decidedly wrong to believe that an excess of lime or arse- 
nic will not harm, for a large excess will inevitably destroy the 
life of the skin. 

Comparing results obtained by arsenic with those obtained 
by sulphide of sodium, both are almost identical as regards 
the removal of the hair proper, but in regard to the loosen- 
ing of the fine-hair there is a big difference in favor of the 
arsenic. Practical experience has shown that skins unhaired 
in limes strengthened with sulphide of sodium are with diffi- 
culty cleansed of their fine- hair. If we are bound to employ 
sulphide of sodium in the limes we must take considerably 
more lime than where arsenic is used, or else we must take 
the chances of injuring the grain by the hard work neces- 
sary on the beam to remove the fine-hair. 

In cleansing skins and hides from foreign matter the skin 01 
hide has always been regarded as a unit, i. e., grain and hide 
substance has been regarded as one. Careful observation 
shows us that this is not correct ; the study of the difference 
in results obtained with sulphide of sodium and arsenic espec- 
ially throws considerable light on this subject. The animal 
hide consists of several dissimilar parts. 



112 THE MANUFACTURE OF LEATHER. 

The hide is made up of the fibro-cellular tissue, or soft albu- 
minous part, the muscular fibres, the grain, and the epidermis. 

The epidermis, or extreme outer layer of the hide, is again 
subdivided into the soft mucous part and the hard horny part. 

The epidermis may be regarded as a cast-off part of the hide, 
which we need not here consider. 

The grain of the hide is of a compact, fine and firm structure, 
while the true skin itself is softer, looser and coarser in struc- 
ture. It is, therefore, possible to properly loosen the true skin 
by the action of the depilatory, while the grain will not be 
sufficiently softened and cleansed. The contrary may, however, 
also be accomplished ; some depilatories will soften and cleanse 
the grain in comparatively short time, while the true skin itself 
will not be sufficiently loosened in this time. It is of frequent 
occurrence that leather is spongy, loose and rotten below the 
grain, while the grain is healthy and strong. This generally 
results from very strong pure liming, the grain having resisted 
the action of the lime longer than the softer true skin. On the 
other hand, we also often come across leather of which the 
inner parts are hard and brittle while the grain is sound. This 
inner rottenness is due to the insufficiently dissolved dirt; it is 
well known that hard rigid leather generally has the most 
handsome, bright grain. This latter case is the result of insuf- 
ficient soaking, insufficient lime, and often partly due to too 
short liming. If the quantity of arsenic-lime has been sufficient, 
it thoroughly cleanses the grain. Particularly evident is this 
difference of structure of grain and true skin manifested by- the 
action of a putrid lime. Here we can readily see that round, 
putrid spots varying in size are formed on the flesh side, while 
the grain shows no symptoms of putrefaction yet. If the pro- 
cess of putrefaction be at this moment interrupted by addition 
of fresh lime, for instance, the resulting leather would be dam- 
aged inside, while the grain would be firm and sound. As a 
rule, however, such putrefaction in the lime is not interrupted 
in time, because if a tanner is so ignorant as to allow his limes 
to become putrid, he will certainly not have sufficient sense 



DEPILATION OR " UNHAIRING." I T 3 

to notice the damage to his stock in time to prevent serious 
trouble. 

If the putrefaction is allowed to progress, it will ultimately 
also injure the grain, which will become manifest by the glossy- 
looking spot which can be punctured by thrusting a finger 
through it as easily as through glue size. We recently came into 
a beam-house where every fifth or sixth skin was so damaged by 
putrid lime. What are putrid limes — perhaps if they are a year 
old? Yes, certainly. But a fresh lime can certainly not be 
putrid. That depends. If the fresh lime is made up with half 
of the old putrid lime liquor, as is often done, then this so-called 
"fresh lime" can cause putrid spots on the skins. We give 
these facts on putrid limes simply to show that there exists 
quite a difference between the grain and the hide proper in 
their property of resisting the action of different agents. 

It will pay to select in the beam-house such skins as are 
wanted for fancy colors, and to work them out well on the 
slating table before tanning. There would possibly be traces 
of lime fat or dirt in the skins if not properly slated, which 
would cause spotty grain. The lime forms with the fat a lime 
soap, insoluble in water, which can be removed only by slating 
and cannot be washed out. This, remaining in the skins, would 
be of no detriment as far as a dull or kangaroo finish is con- 
cerned, but would show up badly in glazing or fancy colors. 

F. E. Atteaux & Co., Boston, Mass., handle sodium sulphide 
in large quantities and would send full directions for its use on 
all kinds of hides and skins on application. 

DEPILATING WITH CHARCOAL. 

In lieu of lime for removing the hair and cleansing the pores, 
charcoal, which is very cheap in parts of the country where 
wood alcohol is made, may be employed either as a substi- 
tute for lime, or the hides or skins may be, as heretofore, 
first partly treated with lime and finally treated with charcoal. 

The carbonaceous matter employed may be either animal, 
vegetable or mineral charcoal in suspension, and it is claimed 



114 THE MANUFACTURE OF LEATHER. 

by William Anderson, of Inverkeithing, near Edinburgh, Scot- 
land, that the results of this treatment are that the hairs are 
loosened, the pores of the skins or hides purified, and the 
putrescent matter, grease and other impurities removed. 

Mr. Anderson states that the most advantageous method of 
carrying this invention into effect is as follows : The hides or 
skins are placed in water of 6o° F., with powdered wood char- 
coal sufficient to give it the consistence of cream, the hides or 
skins being removed and then placed back in the same liquor 
each day until the hairs are sufficiently loosened to yield easily, 
care being observed to stir the charcoal powder which may 
have subsided in the intervals of removal, in order as far as 
possible to keep it in suspension. 

The hides or skins are afterward washed, fleshed and 
scudded as in the ordinary method, when they are ready for 
tanning without other treatment, and the charcoal powder may 
from time to time be revivified by drying it in thin layers in 
the sun or in a current of air. 

In order to render them flat and soft, and to remove lime 
and other impurities from hides or skins which may have been 
treated with lime for the purpose of removing the hairs, the 
process which has just been described may be applied. 

DIPILAT1NG WITH SULPHIDE OF BARIUM. 

Foley invented the following process for treating hides and 
skins previous to tanning, and it relates to removing the hair 
and epidermis from hides and skins of every description, and, 
however cured, softening dried and cured hides and skins, and 
separating the wool and hair from skins in their natural state. 

For unhairing he uses, instead of lime, but in a somewhat 
similar manner, solutions, of sulphide of barium of varying 
strengths, prepared by dissolving in water solid sulphide of 
barium, produced by heating fine ground sulphate of baryta 
mixed with carbonaceous substances to about a white heat in 
a reverberatory furnace or other suitable appliance. 

In treating green slaughter hides and skins to remove the 



DEPILATION OR " UNHAIRING." I I 5 

hair and epidermis, first wash them to remove the blood and 
dirt, and then immerse them in a strong solution of sulphide of 
barium, about 15 Baume, for about three to six hours. They 
are then withdrawn, again washed and taken to the beam-house, 
to be treated in the usnal manner. 

In the treatment of salted or cured hides and skins for the 
removal of the hair and epidermis, first immerse them about 
ten to twelve hours in an old or partially spent solution of sul- 
phide of barium, for the purpose of cleansing them and destroy- 
ing the effect of the salt or substance with which they were 
cured, and afterward immerse them in a solution of sulphide of 
barium of about 6° to 8° Baume for about ten hours, when they 
are ready for the usual treatment in the beam-house. 

In the treatment of dried or flint hides and skins it is neces- 
sary, before the hair and epidermis can be removed, to soften 
them ; this is done by soaking them about twenty-four hours in 
a solution of sulphide of barium that has already been used for 
unhairing, or in a weak solution of about 3 Baume. 

After the dried hides and skins are thoroughly softened in 
all their parts, in the manner above set forth, immerse them, for 
the purpose of removing the hair, and epidermis, in a solution 
of sulphide of barium of about 5 Baume for about six hours, 
and then pass them on to the beam-work. 

In the treatment of skins for the removal of wool and hair, 
apply on the flesh side of the skins, by any suitable means, a 
concentrated solution of sulphide of barium mixed with any 
inert substance, to the consistency of thin paste. The solution 
applied in this manner penetrates the skin, loosens the roots of 
the wool or hair, and allows it to be removed uninjured and in 
its natural condition. 

This invention has advantages over the liming process now 
in use for removing hair from hides and skins and softening 
them, and among others the following are claimed by the inven- 
tor : No part of the gelatinous tissue, grain, or substance of 
the hide is removed or disturbed ; hides and skins are left in 
their natural state and suppleness ; at least twenty-five per cent. 



I 1 6 THE MANUFACTURE OF LEATHER. 

greater weight of leather can be obtained from hides treated by 
this invention than by the old process of liming. The hair, it 
is claimed, is removed in one-twentieth part of the time usually 
employed, thus effecting a great saving in time, labor and ex- 
pense. Hides and skins treated by this invention, and intended 
for upper leather, do not require to go through the operation of 
" bating," which effects another saving in time and expense. 

WORKING-OUT AND UNHAIRING ALL KINDS OF HIDES AND SKINS WITHOUT 
LIMES, BATE, DRENCH OR BEAMING. 

This is the Peirson-Moor process, which has been carefully 
and thoroughly tested and developed during the past three 
years by the North Star Tannage Co., manufacturers of glazed 
kid and other leathers, Philadelphia, who will doubtless testify 
to its value and economy. 

It is claimed for this process that the unhairing can be done 
in twenty-four hours at about one-half the present cost, with- 
out risk or damage to the hide or skin. 

Stone, Timlow & Co., Warren St., New York, control the 
patent, which is dated February 18, 1896. 

There are many other substances which have been used for 
depilating, which need not here be mentioned. 

CHEMISTRY OF DEPILATORIES.* 

A sample of liquor from an old, well-plunged lime pit in a 
tanyard was found after nitration through sand to have a specific 
gravity of 1.0046 at 17. 5 C, and showed a feeble reaction for 
albumin. The total nitrogen was determined in 100 Cc. by 
the Kjeldahl method, and the difference between this value and 
the nitrogen found in the total solid residue was regarded as the 
nitrogen in the volatile bases. To avoid destruction of nitrogen- 
ous matter during evaporation, sodium bicarbonate was added 
in quantity sufficient to carbonate the lime in the liquor. The 
albuminoids were precipitated by feebly acidifying with acetic 

* By J. Von Schroeder and W. Schtnidt-Dumont, in Dingler's Polytechnic Journal. 



DEPILATION OR " UNHAIRING." 117 

acid and warming. Volatile acids were distilled in steam after 
acidifying the liquor with sulphuric acid. Estimation of caustic 
lime proved difficult on account of the organic matter present. 
Analysis of the sediment which settled from the liquor before it 
was filtered gave the following figures: CaC0 3 , 8.22; CaO, 
43.99; CaO combined with organic matter, 8.82; and organic 
matter, 38.97 per cent. 

Since this contained so much free lime it was concluded that 
the liquor was saturated with free lime, in which case it would 
contain 1.299 grms. per litre at 15 C. When shaken with 
lime, however, the filtered liquor dissolved a considerable quan- 
tity, showing that lime had been lost during the filtration 
through sand. 

The following table gives the results of the analysis : 

Grms. per Litre. 

Organic solid matter 1 1.856 

Inorganic matter 3* r 5^ 

Containing CaO* 2.010 

" MgO 0.013 

" alkali sulphates and chlorides 1.130 

Total nitrogen 1 .649 

Comprising N in solid residues !-5 2 7 

" N in volatile bases 0.122 

Total precipitate by acetic acid 2.022 

Comprising fatty acids 0.044 

" ash 0.002 

" albuminoids (14.21 per cent. N) I -97& 

Nitrogen in filtrate from acetic acid precipitate x -37^ 

Volatile acids (as acetic acid) 0.480 

Organic matter not precipitated by acetic acid (containing 

13.41 per cent. N) 9.354 

* After having been shaken with lime the liquor contained: 

Grms. per Litre. 

Free CaO 1.299 

Combined CaO 1.678 

Total 2 -977 

The volatile bases present had the odor of trimethylamin* 
and the volatile acids that of caproic acid. The authors do not 
think that they have sufficient evidence to enable them to pro- 
nounce upon the nature of the albuminous organic matter. 



Il8 THE MANUFACTURE OF LEATHER. 

Experiments here described in which lime and sodium sul- 
phide were together dissolved in water led to the conclusion 
that each of these two compounds retains its individuality 
when in solution in the presence of the other ; hence it may be 
deduced that the simultaneous application of lime and sodium 
sulphide for unhairing, whether in the form of a solution or of 
a paste, is beneficial, because each exerts its specific action on 
hide and hair, not because there is a formation of caustic soda 
by double decomposition, as has been supposed. The lime 
probably also serves to protect the sodium sulphide from de- 
composition by any carbon dioxide which may be absorbed. 

For the proximate analysis of red arsenic, the authors 
recommend that the arsenious oxide should be extracted from 
20 grms. of the sample by digestion at a gentle heat with 200 
c. c. of hydrochloric acid (5 per cent.) for 5 'hours. The solu- 
tion may then be oxidized by nitric acid and evaporated to dry- 
ness, the residue being heated at 400 C. for 45 minutes and 
weighed as arsenic anhydride. To separate As 2 S 3 from As 2 S 2 , 
10 grms. of the portion from which the As 2 03 has been ex- 
tracted may be shaken at the ordinary temperature with 200 
c. c. of ammonia (2 per cent.) until no more arsenic is dis- 
solved ; an aliquot portion of the solution is evaporated to dry- 
ness and the Asi,S 3 weighed. A sample of red arsenic thus 
examined gave : As^S 3 , 73.56 per cent. ; AS2S2, 26.1 1 per cent. ; 
As 2 3 , 0.37 per cent. 

To investigate the part played by red arsenic in the mixture 
of it with lime which is commonly used as a depilatory, 40 
grms. of lime and 8 grms. of red arsenic were made into a thin 
magma with 160 c. c. of water, this magma was heated on the 
water bath for one hour, then made up to a volume of 3150 
c. c. with water, filtered, and the solution analyzed. It was 
found that 4.13 per cent, of the arsenic, 93.50 per cent, of the 
sulphur, and 15.25 per cent, of the lime remained in solution. 
The undissolved residue was brown from the presence of un- 
combined arsenic, so that the chief reactions may be repre- 
sented by the equations : 



DEPILATION OR " UNHAIRING." 119 

(i)3As. 2 S 2 +9CaO + 3H 2 0=2Ca 3 CA S 03) 2 +3Ca(SH) 2 +As 2 
(2)2As 2 S 3 +9CaO+3H 2 0=2Ca 3 (As0 3 ) 2 +3Ca(SH) 2 

There is, however, the dissolved arsenic to be accounted for, 
since calcium arsenite was found to be quite insoluble even in 
presence of excess of lime. Experiments showed that calcium 
arsenite reacts with a solution of calcium hydrosulphide, with 
formation of calcium thioarsenite which passes into solution. 
Supposing the arsenic to exist in this form in the unhairing 
liquor, it may be calculated from the foregoing figures that one 
litre of the liquor contains 4.355 grms. of Ca 2 (AsS 3 ) 2 , 27.780 
grms. of Ca(SH) 2 and 1.299 grms. of CaO. It appears then 
that the sole constituents of the lime and red arsenic depilatory, 
which can be considered as active, are the calcium hydrosul- 
phide and the small proportion of calcium thioarsenite, unless, 
indeed, ammonia and amines developed during the sojourn of 
the hide in the mixture can dissolve any of the calcium 
arsenite. This point was settled in the negative by the analysis 
of a liquor which had been used for three weeks for treating 
kips, when it was found to contain somewhat less arsenic than 
it did originally, showing that the amines and ammonia which 
were undoubtedly present had not rendered the arsenic com- 
pounds more soluble. The putrid odor of this arsenical lime 
liquor seems to contradict the common statement that the func- 
tion of the arsenic is that of an antiseptic. 

It remained to ascertain whether the calcium thioarsenite 
possesses any depilatory properties. For this purpose arsen- 
ious sulphide was dissolved in calcium hydrosulphide solution. 
In this solution, containing CaS.As 2 S 3 , pieces of raw hide were 
immersed and kept in stoppered vessels for about a month; 
none of the pieces were materially altered except that each was 
colored yellow throughout ; the hair was as firm as before im- 
mersion, and the hide as soft and elastic. When exposed to 
the air the pieces lost their yellow color, consequent on the 
decomposition of the thioarsenite, and at the same time the 
hair was loosened. The same effect was observed in the case 
of pieces of hide left in the thioarsenite solution in open ves- 



120 THE MANUFACTURE OF LEATHER. 

sels. There was depilatory action, but it was found to be due 
to calcium hydrosulphide, for the arsenic had all separated as 
sulphide and the solution contained Ca(SH) 2 . 

The authors conclude that the activity of arsenical limes is 
due to calcium hydrosulphide and calcium hydroxide alone. 

DEPILATION BY SWEATING. 

Villon claims to have traced the loosening of the hair in the 
sweating process to the putrefactive action of a specific bacte- 
rium which he styles the bacterie pilline. This organism is aero- 
bic and feeds upon the hair substance (pilline), converting it 
into leucine, tyrosine, butyric acid, margaric acid, and ammo- 
nia ; the ammonia dissolves the cori'in and thus swells the hide. 
Villon further claims he has obtained pure cultures of this bac- 
terium on ammoniacal gelatin — ammonia having an inhibitory 
effect upon other bacteria — and to have inoculated sterilized 
hide therewith, when an evolution of ammonia and loosening of 
the hair followed. 

The experiments on which Villon bases his conclusions have 
been criticised on the ground that the method adopted for ob- 
taining antiseptic conditions was not sufficiently drastic. Ster- 
ilization of hide by exposure to a temperature of 50 C. for 24 
hours, followed by ten minutes at 1 io° C. (the method adopted 
by Villon), was found to be impossible. Recourse was there- 
fore had to the use of antiseptics, and carbon bisulphide in the 
form of potassium ethyl dithiocarbonate (potassium xanthoge- 
nate), was employed as being easily removed by washing, and 
not deleterious to the hide. 

The following conclusions are drawn : A dilute solution 
(1 — 0.25 per cent.), of potassium xanthogenate will gradually 
kill all micro-organisms existing in hide from which the hair 
has not been removed, without changing the hide to a percep- 
tible extent, even after half a year's immersion. A short expo- 
sure (24-48 hours) to this antiseptic will prevent general putre- 
faction, but will not destroy a streptococcus which by decom- 
posing the rete malpighii, loosens the hair. The organisms 



DEPILATION OR " UN HAIRING." 121 

which remain active in this way evolve ammonia without any 
marked quantity of other odoriferous compounds, and are ap- 
parently killed, before there has been any attack on the hide 
fibre, by the decomposition products of the rete malpighii cells. 
The identity of these micro-organisms with a known form re- 
mains to be proved : so far, a tendency of the colonies to 
develop in the form of an intricate and extensive network seems 
to characterize this streptococcus. 

It is proposed that, in the very probable event of the pure 
culture of the bacterium which is responsible for the loosening 
of the hair in the sweating process being obtained, a rational 
system of sterilizing the hide by carbon bisulphide vapor and 
then inoculating it with the necessary bacterium shall be fol- 
lowed by the tanner who unhairs by sweating. 

In the preliminary preparation of sole leather we use the 
" cold-sweat " process, while in Great Britain and other portions 
of Europe, the warm-sweat method is employed ; but for the 
production of upper leather, the hides are limed about as we do. 

Dry flint hides are the ones that are usually prepared in this 
country by the employment of the sweating process for depi- 
lating, and it is highly essential that the hides should be prop- 
erly soaked, and all their parts be thoroughly softened before 
they are subjected to the sweating process, for if not intelligently 
prepared, they harden in spots, forming " old grain." 

" Frieze" is principally caused during the process of sweat- 
ing when the grain of the hide is inclined to be tender and has 
the appearance of being scraped off. "Black spots" or " old 
grain " are blotches of dark color, and when the hide is tanned, 
rolled hard, and finished these spots cannot be buffed off, and 
sometimes they extend over the whole side of leather, as has 
been stated in the chapter treating of the soaking and softening 
of hides. 

A BUILDING FOR SWEATING HIDES OR SKINS. 

The arrangement shown in Figs. 18, 19, and 20 for sweating 
hides and skins, is the invention of Mr. William M. Mason, of 



122 



THE MANUFACTURE OF LEATHER. 



Buffalo, N. Y., and the valuable points which it contains will be 
readily appreciated by tanners who employ the process of 
sweating. 

Fig. 1 8 is a sectional elevation of a building embodying the 
improvements. Fig. 19 is a horizontal section in line x x. 
Fig. 20 is a vertical section at right angles to Fig. 19. 

Fig. 18. 




This invention consists of a vault or apartment having a ven- 
tilator provided with a regulating valve, and a water-floor con- 
sisting of a series of communicating-troughs, arranged and 
operating as hereafter described, for the purpose of softening 
dry hides and sweating the same. 

In the drawings, A represents a building of any kind, and B 
is a ventilator at the top. If the whole building is used as the 
vault, the ventilator simply extends from the top, as in black 



DEPILATION OR " UNHAIRING. 



123 



lines, Fig. 18, but, if only one story is used, the ventilator is 
extended below and passed through the flooring, as shown by 
the dotted lines, thereby leaving the upper story or stories free 
for other uses. A valve, a, is preferably hung in the ventilator 



Fig. 19. 




at any point, and provided with cords b b, by which it is ope- 
rated. The use of the valve is to graduate the escape of the cur- 
rent from the interior, by closing more or less of the ventilator 
space. Any desired number of the ventilators may be used, 



Fig. 20. 



S 



A 



k 



& 



ng* Kg* ea ^ ra ^a p^, p& tsa e^ v?% m ct pa 



1\\\\\\\\\\\\\\^\\\\\\\\\\\\\\\'' 



and they may be extended to any desired height, the latter 
being preferable as it produces an active ventilation. A 
water-floor, C, is employed, to which is applied water to pro- 
duce the evaporation. The inventor prefers the form shown, 
which consists of a series of troughs or water-ways, c c c, open 
at alternate ends, as shown at d d, so as to form a zigzag water 



124 THE MANUFACTURE OF LEATHER. 

communication around, as indicated by the arrows in Fig. 19. 
The water enters by an induction-pipe, f, at one end, and 
escapes by the eduction-pipe, f , at the other end. This cur- 
rent or flow of the water is essential to discharge such gases as 
are absorbed by the water and keep the water pure. Either 
fresh or salt water may be employed ; but the latter is prefer- 
able, especially in hot weather, as it produces a colder atmos- 
phere, and the salt acts as a preservative to the hides in sweat- 
ing. A different arrangement of the water-floor and its troughs 
may be used, and the throwing or spraying of the water on the 
floor might be used with a similar effect, g g g are the slats 
or poles for hanging the hides, h h h are slats laid as a floor- 
ing over the water-troughs, with interstices left between to allow 
of the evaporation. 

By the means above described, there is produced cold sweat- 
ing in contradistinction to the warm sweating heretofore prac- 
tised. By so doing, it is claimed that the requisite dampness 
is always obtained without any danger of heating and spoiling 
the hides. The ammonia and gases are all carried off as fast 
as they are generated, thus removing at once the great cause 
of putrefaction. There is, consequently, no loss of the hides 
from this source, and but little care or time is necessary in 
conducting the operation, as compared with the usual method. 

Any arrangement of doors, windows, or other apertures or 
entrances may be used, and the vault may be so arranged that 
an opening may be made in the same at the bottom at any 
time, for the purpose of admitting air to assist the ventilating 
action when the atmosphere is heavy, as is sometimes the case. 

CARE TO BE OBSERVED IN SWEATING HIDES. 

Some tanners prefer to. maintain the temperature for the 
sweating pits at from 6o° to yo° F. ; but the risk increases 
largely in proportion to the increase of temperature. 

Faithful attention should be paid to the hides during the 
advanced stage of sweating, and when any give indications of 
advancing too rapidly they should be removed to the bottom of 
the pit and properly cared for. 



DEPILATION OR " UNHAIRING." 125 

When the sweating process is used for small hides or kips, 
they should be thoroughly washed in very clean water, spread 
out after four days' soaking, well rinsed and drained, then laid 
together in packs in such a manner that the hair is outward, 
and the pairs of skins back to back. Hang them over the poles 
of the sweating pit, with the tail end upon the one side, and the 
head on the other. Then close the door and stop it up well so 
that the air may be excluded as much as possible, and leave 
matters thus until the odor of the sweating process becomes 
quite strong, which is an indication that the process of depi- 
lation is about to begin, and from this time out the greatest 
attention should be paid to the stock. 

The working of the sweating process is shown by a sharp lye 
which forms under the hair, and which drops off the instant 
fermentation sets in. 

Light hides should not be placed in too strong lime ; these 
hides should rather be operated upon by degrees and always 
with weak lime, after coming from the sweating vault. 

The sweating process regulates and hastens the expansion of 
the hide, opens the pores, and places the hide in a state similar 
to that in which it was at the time the animal was slaughtered. 
To prepare it for the leather dressing process, it will be found 
enough to work the hide lightly on the flesh side with the iron, 
when it is taken out of the sweating vat, so as to stretch out 
the wrinkles that may appear before the hide is placed in the 
lime-pit, which, as has been said, should always first contain a 
weakened lime-bath. 

With regard to the large hides, such as those imported from 
South America and elsewhere, we urgently recommend that 
they should be subjected to the sweating process, for, we repeat 
it, the sweating system has not only the effect of facilitating 
the process of depilation, but of giving to dry wild hides that 
development of which they stand in need. 

Buenos Ayres hides are a species of hide which softens easily 
and in a regular manner. It is admitted that hides which are 
allowed to remain continuously in water soften less readily than 



126 THE MANUFACTURE OF LEATHER. 

those which are alternately soaked and piled. And now let us 
consider how piling compares with sweating. Piling is nothing 
more nor less than a slow inward sweating, and while it is slow 
you run the risk of having the edges damaged, by giving the 
time necessary to effect a good result. So in order to save the 
back and extremities you are obliged to dispense with a com- 
plete softening of the hide, and moreover lose time, which is 
always the result of irregular soak r.r . We seek to attain in 
soaking the hide the raising up of the fibres, in order to save 
those parts of the hide which were wet, and became dried dur- 
ing transportation ; and the best mode of doing this consists in 
accelerating the operation, so as to obtain a thorough soaking 
by the sacrifice of from seven to eight days. 

Stagnant water does not give the dry hide time to become 
completely softened again, at least it injures the grain, which 
becomes lost before the water has had time to penetrate the 
fibres of the hide. 

Under these circumstances, sweating is alone of use, and if 
necessary, a softening during twenty-four hours in open water 
will be sufficient to secure a satisfactory result, as experiment 
has proven. 

Soak the hides in water for twenty-four hours, mark the flesh 
side well, and rinse the. hair side thoroughly, so as to rid it of 
all foreign substances, so that no faulty spots may ensue ; let 
them drain in a heap during four or five hours, and bring them 
to the sweating process as above described. Sprinkle them 
with fresh water from a gardener's watering pot, provided with 
a sieve-like spout, and after the hides have been again allowed 
to drain off, put them back in the sweating vat. 

Three sprinklings with the watering-pot will be found ample, 
in combination with the sweating process, to soften the driest 
and oldest hides to such a degree that, even if they are of the 
heaviest, they can at once be divested of the hair. Then 
separate them after rinsing, lay them again in water, clean and 
scrape them, and do not interrupt the gradual course which 
the hide has to undergo. 



DEPILATION OR " UNHAIRING." \2J 

What we have last above stated should only be resorted to 
when suitable water is wanting for proper soaking, for we 
recommend above all things that the hide be carefully soaked 
in water, as this raises it well ; but in all cases, whichever mode 
of soaking be followed, the hides should never, as a general 
rule, be allowed to stay in the water longer than four days, or 
from five to six days in severely cold weather. Of course the 
sprinkling with a watering-pot is then superfluous, and there 
will then only remain the placing of the hides in the sweating 
vat to be attended to. They should be left in it from four to 
six days, according to the season of the year. 

The operation of the sweating process is decomposition, 
which causes the grain to lose its elasticity, or holding power 
over the hair, so that it may slip off almost involuntarily, leav- 
ing the pelt so soft and flabby that even the advocates for this 
method recommend a lime-bath after, to resuscitate the pelt, 
or what they call raise it, previous to putting in to tan. 

THE WARM SWEATING PROCESS. 

The process of warm sweating largely employed in Germany 
and many other portions of Europe is usually conducted in a 
buried box of suitable size, from which the air is rigidly excluded. 
The box has racks firmly attached to the sides, opposite each 
other, and into which stout notched poles are fitted to receive 
the hides after they are properly rolled. The cover of the box 
is usually composed of loose boards, which are convenient for 
handling in filling or emptying the sweat-box. 

After removal from the water and draining off for a few 
hours, the hides are placed, hair side out, alongside the sweat- 
box, and the sides folded in towards the back, or the hides are 
rolled together from the side towards the back. 

If the sweat-box is of sufficient depth, folding in of the head 
is not necessary, but otherwise it has to be done to prevent the 
hide from touching the bottom of the box. To keep the head 
from sliding out, which might easily happen, both ends of the 
rolled hide are securely tied with twine. After covering the 



128 THE MANUFACTURE OF LEATHER. 

bottom of the box with a layer of spent tan three or four inches 
thick, the hides are hung close together over the above-men- 
tioned poles. The box is then tightly covered with boards 
upon which, to prevent all access of air, tan is piled to the 
depth of about ten or twelve inches, and well trodden down. 
Warm steam is frequently used in order to accelerate the sweat- 
ing process. Though this method offers some advantages, great 
risk is connected with it, and the utmost care must be exercised 
to guard against overheating. Spontaneous heat, which is gen- 
erally developed in five to six days, is always preferable, as it 
acts more uniformly than heat produced by steam. 

After remaining in the sweat-box for a few days, the con- 
dition of the hides is examined by removing the tan from 
one corner and pushing a board far enough back to allow the 
introduction of the hand. If after examining several hides, it 
is found that no heat has been developed, and the hair not 
loosened, the box is immediately closed. With some experi- 
ence and skill it is an easy matter to determine how long the 
hides will still have to remain in the box ; fourteen days being 
frequently required before the hair becomes loose. The great- 
est care and precaution are necessary during the entire sweat- 
ing process, as putrefaction promoted by heat makes rapid 
progress, and may cause great loss. 

SWEATING FRESH HIDES. 

After cutting out the horns, fresh ox hides intended for sole 
leather are spread out and thoroughly salted upon the flesh 
side. After folding each hide in the middle from head to tail, 
and tucking in the shanks, sides, and head, it is formed into a 
pack ; several of these packs are then piled upon one another, 
and covered with woolen covers or straw. It is best to perform 
these operations in a cellar. 

It is advisable to use three pounds of salt for a large hide, as 
this quantity is required to protect the flesh side against putre- 
faction, and besides makes the hides more solid. After twelve 
to sixteen hours the hides are turned. The packs are taken 



DEPILATION OR " UNHA1RING. 120, 

apart, the hides refolded, and again piled up and covered, after 
which they require turning only every three or four days. By 
this method the hair becomes loose in two to three weeks. 

Fresh salted hides are generally not subjected to the sweat- 
ing process, it being preferred to place them, after thorough 
soaking in water, in weak lime, when the hair becomes suffi- 
ciently loose in from six to eight days to allow of the hides 
being unhaired. 
9 



CHAPTER VIII. 

UNHAIRING AND FLESHING BY HAND AND MACHINERY. 

In the United States the unhairing and fleshing of hides is 
done by both machinery and hand ; but the hand method is 
passing away, and it will soon be used only by the small country 
tanners. 

The operations are conducted in the " beam-house," an in- 
terior view of which showing the forms of beams employed and 
other details of the hand method is given in Fig. 21 ; the 
German form of beam and stand, used in tawing establishments 
for skins is shown in Fig. 22, and the unhairing knife in 
Fig. 23. 

After loosening the hair, the hides, if they have been sub- 
jected to the sweating process, are removed from the sweating 
vaults, drawn through fresh water, and allowed to drain. This 
operation prevents drying, promotes cooling off, and interrupts 
putrefaction, and as hides thus treated will usually keep for two 
days without suffering damage, unhairing need not be hurried. 

Limed stock is taken from the " limes " directly to the un- 
hairing beams or to the unhairing machines, and is not passed 
through water as in the case of hides that have been subjected 
to the sweating process. 

The " unhairing " of hides and skins by the hand method is 
usually effected by placing them upon a beam and scraping the 
hair off with a concave blade called the " unhairing knife," 
which agrees with the curvature of the beam, and the operation 
is performed by men of great physical strength, endurance and 
skill, acquired only by long and continued application ; but 
this manner is too slow to meet the large and constantly in- 
creasing demand for leather, and consequently aids in render- 

(130) 



UNHAIRING AND FLESHING. 



131 




,,- IXlli 



s'3 

SIRS 



1? 




132 



THE MANUFACTURE OF LEATHER. 



ing this material too dear for a commodity of such varied and 
indispensable employments, and in order to facilitate unhairing 
a large number of machines have been invented in this country ; 
but of this we shall have more to say later on. 



Fig. 22. 




Fig 23. 




To offer increased resistance to the tool in the hand process 
of unhairing, very fine sand, or road dust, mixed with a small 
quantity of ashes, is sometimes rubbed into the places where 
the hair is difficult to remove ; but this practice is injurious to 
the grain and should not be employed. 

As depilation is more easily accomplished by pushing the 
knife against the hair, the sides from the hind shank towards 
the head are first operated upon and then towards the back. 

Fresh hides are operated upon as soon as the hair can be 
pulled out around the shanks, and from the upper part of the 
head. 

After depilation by hand the hides are again placed in water, 
and rinsed and left to remain over night, after which they are 
usually ready for fleshing. 

In the process of unhairing hides and skins, sometimes some 



UNHAIRING AND FLESHING. 1 33 

of them are cut or so injured that they are reduced from the 
first quality to a lower grade, and thus loss is occasioned. It is 
well known also that after the hair has been removed by the 
usual process of liming and scraping or rubbing it off, there 
remains a short fine hair or fur, and also hair on the edges and 
extremities of the hide, which has to be removed generally 
during the scouring by a sharp knife or other instrument called 
the " short-hair knife." The chief mischief is done to the hides 
in removing the fine hair by cutting or clipping the grain of 
the hide, and when this is too frequently done a guard should 
be attached to the knife in order to prevent the possibility of 
damaging the skin, especially when it is intended for delicate 
work. 

The knife is made of steel, like ordinary knives, with the 
usual handle, but for convenience the blade may be made with 
a double edge, the under side of which is somewhat convex, 
being thickest in the middle and gradually decreasing in thick- 
ness to the edge. The upper side of the blade may have a 
dovetail rib in the middle or thick part of the blade, and from 
this rib to the edge on either side the blade should be some- 
what concave. 

The guard is made with a dovetail groove, so as to slip closely 
on to the rib. It is made of German silver, brass, copper, or 
any suitable metal or material, and should project beyond the 
edge of the blade about the sixteenth part of an inch. Its edges 
should be thick enough, or slightly corrugated on the inner 
side, so as to give it requisite stiffness. 

When the knife needs sharpening the guard may be easily 
slipped off and also ground down if necessary. 

The concave side of the blade and the openings of the guard 
allow the hair to pass off without inconvenience. 

The knife is used in the same way as the ordinary knife, and 
is of great value in cleaning kid-skins and other varieties of 
skins used for glove leather, where so much care has to be 
exercised to prevent clipping the grain. 

In France particular attention is paid to the beam work on 



134 THE MANUFACTURE OF LEATHER. 

calf skins, and we will describe the process of unhairing and 
fleshing as practised in that country. 

The beam-house is so arranged as to avoid loss of time for the 
workmen in taking out of the vats and putting back the skins 
they are working. 

They have at least three vats for five or six beam-hands ; 
these vats have a capacity of 375 or 400 gallons each; the 
water runs into and out of them with rapidity so as to fill and 
empty them promptly. 

The unhairing beams are five feet long, and are covered with 
strong sheet zinc, and thus have a smooth surface convenient 
for the work of the operator, and which avoids breaks and knife 
cuts on the grain side. 

The sheet of zinc is 3 ft. 4 in. long and 2 ft. 1 in. wide ; the 
beam presents a convex line of 7^ inches rise. The zinc is 
fastened with round-headed tacks well nailed down, and must 
be put about 1 ^ inches below the head, for the following 
reasons : It often happens that it is necessary to put for drip- 
ping 35 or 30 skins on the same beam, and to leave them on it 
for several hours, in which case the undermost hide which rests 
on the edge of the head of the beam will have a deep curved 
mark pressed on the neck, and this mark cannot be taken out in 
tanning or even in currying. The grain at that spot looks like 
parchment, and refuses to take the tannin. A prominent French 
tanner tried to discover the origin of these spots, and found 
fhat they had been caused by the sharp edge of the beam-head, 
and he put the zinc about 1 ^ inches further down, and from 
that time he did not find any more of these creases, which had 
previously spoiled the skins and diminished their value. 

The beam for fleshing the skins and for thinning the neck is 
broader, and less arched than the other; it is lens shaped. 
This facilitates the work of the knife, for by having a broader 
surface, the edge is less liable to slip and make flaws, and the 
work progresses more rapidly, as the operator is not forced to 
change the position of his calf-skin so often, and when he reduces 
a throat or a head, he does so in a more uniform manner. 



UNHAIRING AND FLESHING. 



135 



To unhair slaughtered calf-skins fresh from the Paris market> 
the workman lays two large skins at a time on the beam, and 
when of medium size places three ; but when the calf-skins are 
small, places four. In order to avoid scratches and to make the 
action of the knife easier, the workman gives great care to the 
edge, and leaves no trace of hair upon the skins. He then 
places them in water, and rinses them. 

Next a skillful workman cuts the navels and nipples, trims 
the rumps, fashions the breeches and the tails, going entirely 
around the skins, and reaches the neck, which requires special 
treatment. Should there be any flesh left by the butcher on the 
flanks and necks, it is lightly removed with the fleshing knife. 
1 

FLESHING BY THE HAND METHOD. 

This operation, which consists in removing all fleshy and 
fatty matter by means of a sharp blade, requires great skill. In 
some tanneries the work is performed with a fleshing knife hav- 
ing a curved blade, which measures about seventeen and a half 

Fig. 24. 




inches between the handles for the kind used for hides, and 
about sixteen and a half inches for skins ; this form of flesher is 
shown in Fig. 24. 

A workman once accustomed to handling this tool can turn 
out very clean work, but it is far better to use for this purpose 

Fig. 25. 



the so-called German fleshing knife, which has a blade measur- 
ing from twenty to twenty-three inches between the handles, 



136 THE MANUFACTURE OF LEATHER. 

and about an inch and three-quarters wide, and which is shown 
in Fig. 25. 

The German, or spring fleshers, are especially recommended 
for extra clean work ; they make a more satisfactory cut than 
the other styles of fleshers, as the workman is able to readily 
adjust it to the curved shape of the beam, which is a great 
advantage, over the stiff straight-edged flesher cutting on an 
oval or convex surface. 

The spring pating fleshers measure about seveteen inches 
between the handles. 

In the commencement of fleshing a hide is laid escutcheon 
part down over the beam, and shaved the entire width of the 
beam, and as far down as the workman can reach, this hide, 
forming a support which is later on replaced by one entirely 
shaved. The hide to be fleshed next is laid, head down, over 
the beam, and after shaving it, first the entire width of the 
beam, and next the sides, it is turned over and finished by 
shaving the escutcheon. In fleshing the left hand precedes the 
right, and, to prevent injury to the hide by cutting into it, the 

Fig. 26. 




workman should accustom himself to drive the knife without 
stopping, as far as he can reach from the top to the bottom 
of the beam. 

The projecting filaments or shreds, and those parts of the 
borders of the skin which are thicker than the rest, are cut off 
with a sharp knife and the portions thus removed are sold to 
the glue manufacturer. 

For the removal of butcher cuts not accomplished by flesh- 
ing, the smoothing stone often proves a great advantage. 

The saw-toothed flesher sometimes employed for dry hides 
is shown in Fig. 26. 



UNHAIRING AND FLESHING. 1 37 

The turning steels employed are round and three square, 
sometimes the latter style is file cut on one side. The three 
square turning steel is shown in Fig. 27. 

In the portion of this chapter devoted to the unhairing of 
calf-skins, the manner of cutting the navels and nipples, and 
trimming the rumps, etc., of calf-skins was described. Follow- 
fng this operation the flesh sides are gone over with the 

Fig. 27. 



" worker," the skins being pushed crosswise or diagonally, 
starting from the humps of the shoulder. Large calf-skins are 
put on the beam one at a time ; but two skins are put at once 
on the beam if they are of medium size or thin. 

In order to have this work done successfully the workman 
must, by means of short and brisk blows, applied in a kind of 
mowing fashion, get off by main strength all the fleshy and 
parchment-like tissues, from the body of the hide and from the 
sinews of the fore and hind legs. 

The action must be brisk and vigorous on the crupper, where 
the nerve of the hide must be entirely broken ; go over lightly 
on the fore and hind flanks without even trying to take off the 
tissues with which they are covered ; the collar must also be 
managed carefully ; the action must be brisk on the necks and 
heads if there are any tissues. 

In acting in this way the nerves of the hides are completely 
broken on their sinewy parts, and due consideration is given to 
the weak or hollow spots. 

This work is very important, and must be overlooked with 
great care, as the skins that are not worked in the way just 
explained, but which are merely and indiscriminately scraped 
for flesh, never develop themselves well in tanning, refusing 
to absorb the tannin and give poor results in the currying. 

When all the skins have undergone this process they are put 
to soak for six hours in a vat of clear water. 



138 THE MANUFACTURE OF LEATHER. 

Then they are next counter-fleshed, putting two hides at 
once on the beam ; they are again soaked in water for an hour 
or two; they are takan up and gone over with the "worker," 
putting two large skins on the beam, or more if they are small ; 
the flesh side to be upwards. It is very important to have this 
operation well done with the " worker," slight blows at first, 
then heavier, in order to empty and purify them of lime ; then 
the grain is cleaned with a knife of which the bevel must be 
very smooth in order to avoid scratches. 

After these two operations the hides are put to soak in clean 
water for three or four hours. They are then taken in hand 
again and given a last working of the grain on the body of the 
hides only ; are rinsed for the last time, and piled awaiting 
storage in the vats. 

It requires a sure hand to do the fleshing of a calf-skin. 
The work must be done in mowing fashion only, as straight 
heavy blows are apt to enter the skin and leave marks of cuts. 
The butchers do generally enough mischief to the skins with- 
out the tanners adding any more. It requires then some know- 
ledge and experience to avoid all mishaps ; and furthermore 
the tanner's is a rough trade and it requires a pair of stout, 
hard and vigorous arms to make a good beam-hand. 

SOAKING HIDES AFTER FLESHING BY THE HAND METHOD. 

This operation exerts a great influence upon the quality of 
the leather, and is much more highly esteemed in Germany and 
France than in this country. 

After fleshing, the hides are placed in water as clean and 
clear as possible, and if running water is used, a location where 
there is but little current, or none whatever, is chosen. If a 
river or creek has to be used for the purpose, a pole is driven 
perpendicularly in the bottom of the river, upon which the 
hides are successively strung through the ear hole and pushed 
towards the bottom, care being observed to keep them spread 
out horizontally. If the water is deep enough as many as 
twenty hides may be suspended one above the other. To give 



UNHAIRING AND FLESHING. 1 39 

a better support to the pole the end projecting above the water 
is pushed through a strap secured to the bank of the river. 

The hides are drawn up twice daily by means of a hook, 
rinsed off, moved and replaced in the manner described. 

SOAKING HIDES IN A STEEPING CISTERN AFTER FLESHING. 

In tanneries located on a river or connected with a water 
conduit, provision is generally made in Germany and France 
for steeping cisterns, which are of great advantage for the 
preparation of sole and upper leathers. They are constructed 
either of stone or wood and so arranged that the water can be 
admitted and drawn off very rapidly at will. 

After fleshing, the hides are placed in the steeping cistern 
previously filled with fresh water. After 12 hours they are 
moved, the water is drawn off, and the hides, after the admit- 
tance of fresh water, are replaced in the steeping cistern. This 
operation should be scrupulously repeated twice daily to pre- 
vent putrid soaking from making its appearance to the injury 
of the hides. By putrid soaking, which is recognized by a foul 
odor of the water, we understand the assumption of a flabby 
condition by the hides, while on the other hand, with a fresh 
and sound soaking, they feel firm to the touch and smooth 
upon the grain side, and the water has no odor whatever. 

HOW LONG SHOULD THE HIDES SOAK AFTER FLESHING, AND WHAT 
INDICATES THEIR READINESS FOR SCOURING? 

In this country the hides, after fleshing, are soaked for a much 
shorter period than in Germany and France. Hides intended 
for sole leather, with us, are generally allowed to soak over 
night, while in the countries which have been named, the time 
ior soaking is from three to five days, the period depending 
much on the temperature of the water, the hides meanwhile 
being frequently examined as regards their readiness for scour- 
ing. They are ready, 1st, when the fine film still adhering on 
places after fleshing can be readily detached by scraping with 
the finger nail, and 2d, when by pressing with the fingers upon 



140 THE MANUFACTURE OF LEATHER. 

the grain side the indented places remain visible. As these in- 
dications can be most readily perceived after rinsing, it is well 
to make these tests after each rinsing operation. 

Hides intended for the production of upper leather after 
being " green shaved " are placed directly in a bate of hen 
manure and worked sufficiently with a drench wheel, after 
which for about 5 minutes they are worked in a wash-wheel, 
and are then worked over with a hide-working machine and 
are next placed in spring water to soak over night. It is con- 
ceded that the bate neutralizes the lime in the hide and leaves 
this class of leather more pliable than when it is subjected to 
long soaking in water, which while it will extract the lime 
imparts an undesirable harshness to upper leather. 

FLESHING AND UNHAIRING BY MACHINERY. 

The processes of unhairing and fleshing hides as usually per- 
formed are the most laborious operations in the business of tan- 
ning and require the workman to be constantly in contact with 
cold, wet hides, which is very injurious to the constitution, 
subjecting most operators to disease and forcing many to leave 
the business. The fleshing and unhairing of hides and skins is 
now successfully performed by machinery at a cost of less than 
one-third of the hand method. 

After the hides have been soaked they are fleshed before they 
are limed, when machinery is employed, and after the liming 
they are unhaired, and then refleshed to take off the flesh 
" puffed up," or raised by liming, or left on after first fleshing. 
For sole and rough leather the process is the same. A few 
tanners " green shave," or flesh out of the lime, and do not 
flesh out of the water soak at all. 

In Fig. 28 is shown the Vaughn new heavy construction 
beam-house machine for fleshing from the soaks, unhairing, re- 
fleshing from the limes, green shaving, and working out, or fine 
hairing, and largely used by tanners of sole, harness, belting, 
rough, upper or grains, buff, colors, wax, kips or calf. 

It will do all these operations perfectly and completely, and 



UNHAIRING AND FLESHING. 



141 




142 THE MANUFACTURE OF LEATHER. 

the manufacturers guarantee its work to be far superior in every 
respect to that done by hand or any other machine. They will 
send them out on trial to any responsible concern, and if the 
results do not substantiate the above statement, it to be no sale. 

Remember, the builders fit each machine for the work it is 
sent out to do, thereby insuring to every tanner perfect results 
on his own particular class of stock, in his own particular way 
of working it. This their long experience in all kinds of tan- 
neries enables them to do to perfection. It is beyond dispute 
that what would be good work and good results on one kind of 
stock, would be ruinous on another. 

The principle and construction is the best that could possibly 
have been conceived for the purpose. This fact is conceded by 
all. The machine and work being at all times under the per- 
fect control and observation of the operator, who sees the hide 
being worked as the bed carries it through the under cylinder, 
and then just how it has been done as the bed returns to its 
place again, thus each and every hide being worked properly 
and perfectly, and if the desired result is not obtained by once 
passing through, it is readily seen by the operator, who, by 
simply moving the lever, causes it to be worked as many times 
as desired without handling the hide or taking much extra 
time. This is important, and it is claimed can be done by no 
other make or style of machine. 

The cylinders also are a great and important factor in the 
success of this machine, and the splendid work and results they 
give cannot be obtained with any other style or form, as has 
been proved by their years of service, and the many attempts 
to equal them. By their peculiar construction, the hide is 
worked both in length and width atone and the same time, and 
the hide, lying as it does on the drum or bed, covered with a 
soft rubber cushion, is subject to no strain or damage whatever 
on the body, head, flanks or shanks. 

The adoption and sole use of this machine in all the leading 
tanneries of the country, is proof positive of its superiority over 
hand work, or that of any other machine. 



UNHAIRING AND FLESHING. 



143 



144 THE MANUFACTURE OF LEATHER. 

One machine is fitted to do the whole beam-house work if 
desired, so can be used to great profit and advantage by those 
running small tanneries. 

But one operator required. 

Economy of space and power. 

Both quantity and quality of work obtained. 

Will work equally well whole hides, sides, kips and calf. 

Sizes or length of cylinders 54 inches, 72 inches, 84 inches, 
108 inches. 

This machine is built by the Vaughn Machine Company, 
Peabody, Mass. 

The cylinders used with this machine are shown in Figs. 29 
and 30. 

The success of machinery for working hides, skins or leather 
depends on the cylinders used, and it will at once be seen by 
these cuts why the Vaughn machines are so superior to hand 
work, as by their novel construction the blades are working 
the stock both lengthways and sideways at the same time. 

The builders vary the form and material of them according 
to the work required for them to do. 

Fig. 31 shows a grinding lathe or cylinder and roll sharpen- 
ing and turning up machine, made by the Vaughn Machine 
Company, Peabody, Mass. 

As will be seen by the cut, this machine works much like an 
ordinary lathe, excepting the cylinder runs in bearings the 
same as when at work in the machine (instead of on centres as 
would be the case in using an ordinary lathe), therefore it is 
bound to be kept perfectly true for the work in the machine in 
which it is used. 

The builders use this machine for sharpening the cylinders 
of their machines where the emery dust or grit of the automatic 
grinder on the machine would be a detriment or cause damage 
to the stock, as by using this all the above is kept entirely away 
from the machine and stock being worked. 

It is a valuable machine to have where Belt Knife Splitting 
Machines are used, as it will keep the rubber rolls perfectly 
true and in fine condition. 



UNHAIRING AND FLESHING. 



H5 




146 



THE MANUFACTURE OF LEATHER. 
UNHAIRING MACHINES. 

Fig. 32. 




WHITNEY'S " JUMBO " UNHAIRING MACHINE. 

Fig. 32 illustrates Whitney's patent double-acting unhairing 
and hide-working machine. It is made in four sizes: 52 
inches, 64 inches, 82 inches, and 109 inches. 

This machine (familiarly called "Jumbo,") differs from the 
original well-known Whitney Unhairing Machine in this respect : 
it is made to feed the hide both ways, unhairing it when it is 
feeding into the machine, and working it when it is feeding out, 
thus effectually cleaning it (especially the shanks and end 
pieces) at one operation. As no part of the hide jumps through 
the machine, no part escapes a thorough working. 

In operating the machine the hide is laid upon a traveling rub- 
ber apron which carries it to the " bite " between the two upper 
feed rolls, and the apron supported by the lower feed roll, 



UNHAIRING AND FLESHING. 1 47 

thence to the work roll filled with slate blades housed at back 
of machine which revolves against the hide at a high rate of 
speed, thus thoroughly cleansing it. After the hide has passed 
half way through the machine, the operator reverses the feed 
and the hide is fed outwardly into his hands, when he turns it 
and works the other half in the same way as first half. 

It is obvious that particular hides may be worked over sev- 
eral times, or they may be fed right through as in the old-style 
unhairing machine, and may be left at either front or back of 
machine when sufficiently worked. 

The shipping mechanism is very simple and works without 
noise or jar. It consists of two loose belts running in opposite 
directions, which, when alternately tightened, drive the feed 
gearing. Either belt is tightened by throwing the weighted 
lever attached to the swinging binder frame to one side or the 
other off its centre of gravity, the working belt being made 
sufficiently tight by adjusting the ball weights so as to just throw 
it over the centre. 

The belts are made double and endless, and should be each 
57 inches long. If they stretch from use they can be adjusted 
by lowering the frame to which the binder pulley shafts are 
attached. 

This machine will unhair and work out 75 to 100 sides per 
hour. It is in use in many tanneries. It takes but a small 
amount of power. The slate roll is so constructed that it will 
not cut or scratch the hide in the least, and the slates can be 
quickly replaced. They are the best quality and not easily 
broken. Steel bladed work rolls are furnished with the ma- 
chine in place of slate when so ordered. 

This machine is made by the Whitney Machine Co., Win- 
chester, Mass. 

The machine shown in Fig. 33 is particularly adapted for use 
in small tanneries. It is really three machines in one. It will 
both flesh, unhair and work out 250 sides per day. It can be 
adjusted to do different kinds of work by simply taking out 
the fleshing roll, and substituting an unhairing or a working- 



148 



THE MANUFACTURE OF LEATHER. 



out roll, which operation takes but a few moments. It is per- 
fectly noiseless in its work. 

When used for fleshing, this combined machine fleshes the 
hide in the same manner as the regular fleshing machine. 

whitney's patent combined unhairing fleshing and working-out 

MACHINE. 

Fig. S3. 




In quantity and quality of work both machines are equal. For 
economy in the use of power and simplicity of operation, there 
is no better fleshing machine in the market than the Whitney 
machine. It has been adopted by many leading tanners. 



UNHAIRING AND FLESHING. 



149 



For unhairing, this machine can be altered so as to feed a 
hide over a table into the machine from one end to the other 
without reversing it, the same as hides are fed into the regular 
unhairing machine. 

For " working out," the combined machine is unexcelled. It 
can be furnished with either of the various kinds of steel or slate 
working out rolls, as may be best adapted to the special kind of 
leather to be produced. Special Slating Rolls are made to order 
by the Whitney Machine Co., Winchester, Mass. 



Whitney's patent re-fleshing machine. 
Fig. 34. 




150 THE MANUFACTURE OF LEATHER. 

The machine shown in Fig. 34 is made in four sizes: 52 
inch, 64 inch, 90 inch and 109 inch, and it is designed to re- 
flesh, or " cut over," the hide after it has been limed or unhaired 
arid once fleshed out of the water soak. This operation takes 
off the flesh "puffed up" by liming or left on after the first 
fleshing. As the hide is in a slippery state, it spreads very 
easily, and there is no danger of cutting it. The feed rolls are 
so constructed as not to injure the hide in the least, and yet are 
so powerfully arranged as to hold and feed the hide without the 
aid of clamps of any kind. 

The operation of re-fleshing saves the tan-liquor, which 
otherwise would be wasted tanning refuse. Without cutting 
into the hide in the least, it leaves it so clean as to save the 
operation of skiving and the expense of maintaining a skiving 
machine. After re-fleshing, the hide will more quickly take the 
tan liquor, and a heavier split can be obtained. 

The capacity of this machine is from 800 to 1000 sides per 
day of heavy hides, or from 1400 to 1800 skins. It is easily 
operated by an ordinary beam-house workman. 

In operation, a hide is thrown into the machine over the two 
front feed rolls (see cut) which are in a state of rest. Foot 
pressure on the treadle swings the two feed rolls, with the hide 
upon them, up against the cutter roll, and also binds the hide 
over a middle feed roll housed in the frame of the machine. 
Just as the hide comes in contact with the cutter roll, the feed 
rolls commence to revolve outwardly and pull the hide against 
the cutter roll and into the operator's hands. After the first 
half of the hide is re-fleshed, the second half is cleaned in the 
same manner. 

This machine is noisless in operation, simple and substantial 
in construction. It takes from three to four horse-power to 
drive it. The cutting cylinder blades are made of the best 
hardened steel, and are sharpened by a patent grinder attached 
to the machine. 

This machine is built by the Whitney Machine Co., Win- 
chester, Mass. 



UNHAIRTNG AND FLESHING. I 5 I 

The craft of the tanner is one which dates from time imme- 
morial, but of recent years great strides have been made in the 
advancement of the art. New ideas have come to the front, 
and better leather is now being made and at a lower cost of 
production than ever before. At present, more attention and 
thought are being devoted to this department of the trade; 
competition and the demand for a better and greater variety 
of leather has made it necessary. 

The tanners of the past have been proverbially unprogressive, 
and it is now only in the face of severe competition and dimin- 
ishing profits that they are waking up and asking, " What can 
we do to be saved?" The answer is to economize in every 
way that it is possible to practice economy. 

The tanner of to-day must be alert and constantly on the 
lookout for new and improved processes and machines and 
adopt them when found, for it is only in this way that he can 
keep abreast of the times and make a profit. 

There are tanners who still unhair and flesh by hand because 
the machines they tried years ago for these purposes were 
crude and unsatisfactory, and they forget that the modern 
machines are not only successful but decidedly economical 
in use. 

It has been demonstrated that the unhairing and fleshing 
machines are now a practical success, and in many tanneries 
the beam men have disappeared, the machines having taken 
their places, saving to the manufacturer fully two-thirds of the 
cost of unhairing and fleshing. 

Small tanners have an idea that they can not afford to buy 
beam-house machinery — this is a mistake, as one machine of 
small size can be purchased which will not only unhair but 
flesh, work-out, re-flesh or " cut over," and do a great many 
other desired things by simply changing the roll. 

Tanners in small country yards will not long continue to 
unhair with the knife over the beam — this is not always thor- 
oughly done, particularly in dressing leather which has to go 
through bates. Men say, "Oh, it will come out in scudding;" 



152 THE MANUFACTURE OF LEATHER. 

but we would say, unhair them clean, and most of the scud will 
leave the skin in the first stage, it will pure better, and be less 
flabby in the offal, and for sole leather it will be better color, 
and better quality. This should be a great consideration, but 
it is much overlooked. We regret to know the practice is to 
get over the work, not how well it may be done. 

Unhairing by machinery is a great acquisition, and much 
more dependence can be placed upon the regularity of the 
work, and less danger of the grain being injured by cuts and 
scratches. A great writer truly said English and American 
workmen are not so painstaking as Continental workmen, but 
every part of manufacture requires this painstaking, or perfec- 
tion will not be attained ; neglect in any one stage cannot be 
compensated in the following ones. For instance, if a part of 
the pelt is not thoroughly softened in the soak, the depilator 
will harden it, the hair will be difficult to remove, and the 
tannic acids will not penetrate so as to amalgamate and chem- 
ically unite — the leather will be hard and shelly. 

Unhairing and fleshing by machinery seem to start the pelt 
right, it goes through the tanning process right and comes out 
right in the finishing. 



CHAPTER IX. 

BATING. 

THE operation of immersing hides and skins intended for the 
manufacture of pliable leathers, in an alkaline solution consist- 
ing of the dung of chickens, pigeons, dogs, or in bran water, or 
in any of the compounds intended to supersede the dung solu- 
tions, or to be used in combination with them, is termed either 
"bating," "abating," " grainering," " reducing," " drenching," 
or "puring." 

The greatest risk in any beam-house is that of bating, mainly 
for two reasons, either that of over-bating or insufficient bating. 

The one is as bad as the other, for in either case the leather 
when tanned will not bring full prices. Because where leather 
has been underbated, the stock still containing lime is bound to 
produce hard, brittle and cracky leather, and, if fancy colors 
are desired, uneven coloring is the result. No stock not thor- 
oughly freed from lime can possibly make good or standard 
leather. Now, on the other hand, if stock is overbated, the 
result is loose-grained and spongy leather, which also com- 
mands a poor price. 

This great risk, which plays so important a part in every 
tannery, is recognized by all tanners, and many patent bates 
have been sprung upon the market to live but a short life, for 
the same trouble was found with them as with the various 
manures and bran, viz. : that beamsmen could never control 
the bate, and it kept them in a constant strain of mind as to 
whether this or that pack would come out right or not. 

It does not seem, strange, therefore, that the theory and 
practice of the beam-house preparation of hides and skins 
should have remained practically unchanged for centuries. 

( i53 ) 



154 THE MANUFACTURE OF LEATHER. 

While chemistry has invaded the domain of so many other in- 
dustries and wrought wonderful and beneficent improvements, 
it is only within very recent years that the tanner has been 
willing to concede that chemistry had anything to do with the 
art of leather manufacture. It is, nevertheless, true that the 
whole science and art of tanning rests upon and is dependent 
upon chemical action and reaction. For this reason many able 
chemists have within recent times directed their attention to the 
scientific investigation of the processes connected with the tan- 
ner's art, with the result that much has been learned regarding 
the technology of these processes, and the tanner has been 
given explanations covering the " why and wherefore " of his 
methods, which should be invaluable to him in the prosecution 
of his business. It is a melancholy fact, however, that the 
tanners as a class are reluctant to countenance new ideas and 
suggestions which run counter to their, preconceived notions, 
and are prone to cling to the old ways and to belittle the efforts 
of scientific men, who would help them to a better understand- 
ing of their trade and would give them valuable aid in advanc- 
ing them toward improved methods. 

It is a standing disgrace to leather manufacturers that they 
have for so long a time adhered to the practice of using manure 
bates for the purpose of removing the lime from hides and 
skins after they have been unhaired. The use of a manure bate 
is not only an extremely disgusting operation, but it is also a 
highly dangerous proceeding, for the hides and skins are more 
or less liable to injury or damage from the moment they are 
placed in such a bate. It has been ascertained and proved 
beyond a doubt that the action of a manure bate is due to an 
energetic fermentation, producing innumerable bacteria, which 
eat away, deplete and dissolve the hide substance, and if skins 
are left long enough in such a bate they will entirely disappear. 
This fermentation also produces several of the weak organic 
acids, which together with the ammoniacal salts present in the 
manure, combine with the lime, forming soluble lime salts that 
are removed from the skins by subsequent washing and work- 



BATING. I 5 5 

ing on the beam, The same may be said of a bran bate ; the 
fermentation of the bran producing acetic, lactic, butyric, and 
similar organic acids, which form soluble salts with lime ; but 
these same acids moreover act as solvents of the hide tissue, 
and the result is the formation of a nidus for the propagation of 
myriads of bacteria which attack the gelatine of the hide sub- 
stance. If the operation of manure bating and bran drenching 
is not carefully watched and properly conducted, serious dam- 
age is often encountered which entails irreparable loss to the 
tanner ; this being especially true where skins are intended to 
be colored and finished on the grain. The " puer run " grain is 
well known to tanners, and they are only too well acquainted 
with the discouraging losses they have met with on this account. 
It is unnecessary to go into details as to why the lime or 
other alkaline depilatories should be removed from hides and 
skins previously to tanning; it being sufficient to say that it is 
agreed upon all sides that it is a necessity to perform this ope- 
ration in order to obtain good merchantable leather. Now it 
is plain that subjecting skins for this purpose to animal putres- 
cent and vegetable fermenting solutions is objectionable, and it 
is equally evident that a working substitute that would do away 
with the undesirable features of these solutions would be a ver- 
itable blessing to the tanner. There have, of course, been many 
substitutes proposed and many patents issued to inventors cov- 
ering processes for bating, but they have all been more or less 
based upon the idea of producing a ferment that would act upon 
the skins in much the same manner as the old processes. The 
attempt has been made to build up by synthesis a substance 
that would contain the essential elements found by analysis to 
be contained in the dog, hen and pigeon manure. A com- 
pound made of old cheese, sal-ammoniac and glucose has been 
used. But such preparations all have the defects inherent in 
fermentive processes. From a purely chemical standpoint a 
dilute solution of an acid known to form a soluble salt with 
lime, such as hydrochloric acid, would seem to be all that is 
required ; but in practice it is found that the action of such 



156 THE MANUFACTURE OF LEATHER. 

mineral acids causes intense swelling, and the hide assumes a 
transparent, gelatinous appearance, and loses its fibrous charac- 
ter, thereby rendering it unfit to be converted into leather. 
Nevertheless an acid of some sort is theoretically the proper 
thing to use ; but it must be an acid that will not disturb the 
fibrous nature of the hide, that will form soluble salts with alka- 
line bases, and that will not induce nor support fermentation ; 
in other words, such an acid must be antiseptic and preservative 
in its action, while at the same time it performs all the other 
functions of a bate. After a long series of investigations and 
laborious experiments in search of such an acid, Mr v Peter S. 
Burns and Mr. Chas. S. Hull, of the Massachusetts Institute of 
Technology, discovered that the naphthalene sulphonic acid 
possessed all the properties requisite for such an antiseptic bat- 
ing andpuring acid. They applied for and obtained a patent 
for the use of this material for bating purposes in 1891, and the 
patent is now owned and the material manufactured and sold 
under the name of " 0. T. Bate" (coal tar bate), by the Martin 
Dennis Chrome Tannage Co., of Newark, N.J. This " C. T. 
Bate" has now been long enough in use to have its merits tested 
most thoroughly, and it has been found to fulfill all the expec- 
tations entertained concerning it as the long looked-for substi- 
tute for the nasty, offensive and old-time manure bate. In its 
commercial form the " C.T. Bate" is solid, but it is readily sol- 
uble in water. Only a weak solution is required to perform its 
work as a bate ; it is cheap, clean and agreeable to handle, is 
not poisonous, and the hides coming from the bating solution, 
ready for the tan liquors, are smooth, soft and white, without 
having lost any hide substance in the bate, and with the grain 
intact. Since the introduction of the " C. T. Bate" there have 
been other acids proposed and claimed to have a similar charac- 
ter for bating purposes. Prominent among these is a mixture 
of acetic and lactic acids, but these acids do not resist fermenta- 
tion, but rather promote it ; besides, acetic acid is a solvent for 
gelatine, while lactic acid, according to Fownes, in the presence 
of water and a ferment like animal membrane produces lactous 



BATING. I 5 7 

fermentation with the formation of butyric acid, which is a power- 
ful solvent of hide substance. Another material under the name 
of " borol" has been patented in Germany for bating purposes, 
ascribing to it lime-dissolving and antiseptic properties. It is 
obtained by melting boracic acid with bisulphates of the metals. 
In a description of "borol," it is stated that "in an anhydrous 
state it represents a vitreous mass, which becomes opaque by 
absorption of humidity; it dissolves readily in water; it tastes 
and reacts acid, is to a high degree a solvent of lime, and pre- 
vents putrefaction." In 1894 a patent was issued to P. Hauff 
in Germany for the use of sulphonic acid for removing lime from 
hides and skins, but this was fully anticipated by the patent 
issued to Burns & Hull in 1891 in the United States. In fact, 
it looks as though Hauff appropriated the American patent out- 
right, but priority of invention in one country destroys the valid- 
ity of a patent in another country, and therefore Hauff is not 
entitled to the discovery of this most valuable material. It is 
certain that American inventive genius is a long Way ahead in 
discovering and applying new methods in the industrial arts 
that save both time and labor in production ; and it is hoped 
that this new American process of bating will sooner or later 
come into general use, to the great advantage and profit of our 
leather manufacturers. 

Bating should always be done in a paddle, as the stirring 
motion allows the stock to free itself of lime, and never should 
be done in a stationary tub. 

There are a large number of tanners who still stick to the old 
form of manure bates, and for their benefit we make the follow- 
ing suggestions and offer such substitutes as occur to us : 

High-limed goat skirls will not stand much pure. Wash 
skins from lime in water in which a little sal ammoniac 
(chloride of ammonium) is dissolved; this will remove con- 
siderable of the lime ; then give them a light pure. 

If the problem was merely to remove the lime still remaining 
in the stock, the operation would be an exceedingly simple one. 
For example, the stock could be treated to a dilute solution of 



158 THE MANUFACTURE OF LEATHER. 

some ammoniacal salt such as chloride of ammonia (sal am- 
moniac). This would remove the lime, leaving the stock white 
and seemingly clean. Or very dilute muriatic acid would be 
effective for this purpose. The fermentive action of the bate 
must be considered its essential property. The skins them- 
selves ferment with the bate, and as considerable gases are 
developed and become entangled in the skins they rise to the 
surface of the liquor and are thrown out of the action of the 
bate. The operation is therefore to some extent automatic, 
for if they should fall in the bate again, as they sometimes do 
when a thunder-shower comes up, they would have to undergo 
a further ferment before raising, and under such circumstances 
would be over-bated and probably run on the grain. 

This fermentive action is of course dangerous. 

The ferment developed produces weak organic acids which 
act upon and dissolve the lime ; at the same time the stock is 
reduced, becomes soft and slippery, the pores are opened so 
that the dirt, lime, greasy soap, fine hairs, etc., can be worked 
out freely upon the beam, thus thoroughly cleansing the stock 
preparatory to tanning. 

The best time for fine-hairing is after the drenching, as the 
grain of the skins is then cleaner, and the fine hairs more easily 
seen. This enables the workmen to get better results. 

Pigeon manure is considered the best bate for calfkid and 
sides, and should not be used over 95 degrees in winter and 90- 
degrees F. in summer. The bran drench should not be above 
the temperature referred to, and is used in all kid-tannages ex- 
cept chrome. 

The period which the hides or skins remain in the bating 
solution is dependent upon the temperature of the bate and the 
thickness of the material subjected to its action. 

Borax and boracic acid make good bates when dissolved in 
water; they work out the lime, but do not eat away the hide 
substance. 

Puring as conducted by manufacturers of light leathers, is 
done for the purpose of removing the lime from the skins and 
preparing them for tanning. 



BATING. 159 

The method pursued is to ferment an emulsion of bran, 
middlings or flour, till it is quite acid, then putting the pelts or 
skins into this fermenting mixture. The acids formed by the 
fermentation make soluble salts of lime in the skins, and the 
bulk of water dissolves the salts of lime out of the skins by the 
subsequent washing. During this operation there is quite a 
quantity of carbonic acid gas generated which, collecting under 
the skins or pelts, causes them to rise. When the skins are 
first thrown into the drench they sink to the bottom, but as the 
fermentive action generates the carbonic acid gas, they come 
to the surface, and the liquid becomes covered with a white 
foam. This has no connection with the drenching proper, 
being only an effect of the fermenting action and the liberation 
of gas. The workmen can best judge when pelts are drenched 
by their appearance and feel. There are several objections to 
this fermentation of bran for drenching, it being a dirty, long 
and uncertain operation. The decomposing ferments that 
break up the starch in the bran into acids permeate the skins, 
and are carried over into the tanning liquids, causing an acid 
fermentation in them. There is also a risk of weeds, etc., which 
contain tannin, being in the bran or middlings, depositing a 
certain amount of tannin in the skins while in the drench bath, 
causing spotted and cloudy results in the tawed or tanned 
stock which afterwards produces uneven coloring. Drenching 
is an essential operation to the preparation of nice leather. To 
leave any lime in the stock makes hard, brittle and cracky 
leather. 

In tanning with salts and alum it is absolute ruin, as the 
alum loses some of its sulphuric acid, making sulphate of lime 
(common gypsum), which makes the skins harsh and hard, it 
being almost impossible to soften them. 

To leave lime in the skins to be tanned with tannin or other 
vegetable extracts means the production of brown spots, darker 
color and a brittle grain. Leaving lime in skins to be used in 
the chrome process means the production of sulphate of lime 
in them, due to the acid used in the first bath with bichromate 
of potash, also producing a brittle grain and hard leather. 



l6o THE MANUFACTURE OF LEATHER. 

The removal of lime is essential in making good leather, yet 
to remove it by means of the bran drench is dirty and trouble- 
some. 

Hides that are intended for sole leather are generally, after 
they are unhaired and fleshed, merely washed or rinsed, then 
immediately put into tan liquor, and handled until colored, then 
shifted on consecutively. Some tanners who have the facility, 
cleanse them more, and by this means get a better color, but 
still there is a large quantity of lime in the interior, which sours 
the liquors, and if they are not soon removed from it, the hide 
gets soft and flabby by the loss of gelatine which it causes. 
This would be prevented if the hides, after fleshing, were put 
into a bath that would extract the lime, and yet extend the 
fibrine, so that it grows continuously, and after well scudding it 
will be more developed, and better fitted to imbibe tannic acid. 

Dressing leather is universally bated in the United States, 
and many other countries, but it is supposed no bates are used 
by the French, who excel all others for qualities of upper 
leather. It should be said they do not use excrement, which 
we say cannot be done without, yet we have seen upper leather 
manufactured in the United States without its use, far superior 
to any where it has been used. We know that where lime is 
used for depilating, it must be extracted before good upper 
leather can be made. This should be done by a non-impover- 
ishing agent, so that the hide is not reduced, but is left with 
the whole body to be matured and utilized. 

When the unhairing has been properly done, all hides and 
skins should be properly cleansed from the depilatory agent, 
whatever that agent may have been. Lime is not so deleterious 
to sole leather as to offal used in some countries for insoles, 
but still it defiles the liquors and does not improve the sole 
leather. All sole leather should be thoroughly cleansed from 
lime ; however, we would not advise that sole leather be bated 
with the excrement of animal, which destroys a large percent- 
age of the gelatine. A good bate for sole leather and one 
which is used in many of the large tanneries of this country, 



BATING. 1 6 1 

although kept a secret, is that discovered by Trumbull in 1847, 
which consists of sugar, or molasses ; the proportion used being 
about 6 pounds to 100 gallons of water. This solution forms a 
soluble saccharate of lime. We have seen some excellent sole 
leather produced by the use of this bate, a much greater addi- 
tional weight being secured than could otherwise be obtained. 

The object should be to cleanse the hide or skin from the 
deleterious materials used in the unhairing process. We pre- 
fer the term puring, i. e., get the hide or skin pure from all 
alkaline matter without decomposing it. It will then be full, 
soft, and velvety, instead of an empty rag. We read some- 
times that a calf -skin should be so reduced that you may pull 
it through a finger ring ; but, to test this, let a calf-skin be 
tanned as it comes from the butcher. After cleansing well 
from the blood and dirt, can it then be pulled through a large 
ring, and will not the leather be firm, stout, and good? 

The practice of reducing the hide or skin is so universal 
among tanners and so consolidated, that it requires electrical 
agency to dispel the illusion ; even those who are the most 
desirous to get an improved mode of puring hides and skins 
from the depilitant, cannot believe it can be accomplished if 
the pelt is not reduced so as to leave it a mere rag, as is done 
by excrement bates, which consume the gelatine while com- 
bining with the lime. 

It is useless for us to profess anxiety for improvements in our 
manufactures and expect to find our goods acted upon by im- 
proved methods to appear the same in every stage as they do 
by old methods, if the altered mode produces no different ap- 
pearance. What different result can be expected at the finish, 
and as bating has much to do with weight and quality, how can 
weight and quality be improved, if the pelt is persistently 
reduced? 

What are the impurities but lime, fat, and dirt, commonly 

called scud, and the fine undergrowth of hair? But even the 

undergrowth of hair should have been so loosened by the 

depilitant that no difficulty should arise in removing it in scud- 

11 



1 62 THE MANUFACTURE OF LEATHER. 

ding. The lime and fat should be assimilated by the pure, 
which with the dirt would form a kind of soap, and would yield 
to the scudding knife and leave the pelt intact without reduc- 
ing it, as all usual bates do by attacking the fluid gelatine 
which it draws from the hide or skin. And from force of habit 
tanners say it is properly reduced or bated, and if this fluid 
gelatine is not extracted, they say it is not sufficiently reduced 
and will not make good leather for the purpose required. 

The time is approaching when this axiom will be discarded. 
The necessity is even now apparent by the large imports of 
light leather taking the place of goods that we manufactured 
ourselves in olden times for our own consumption. Very light 
goods are required for some branches of the trade, and it is 
said this can only be got by reducing the skin in the bate ; but 
if the proper skins were selected and manufactured with the 
whole constituents left in, superiority would be obtained, for 
the fluid gelatine is the lubricator of the fibrines in life, and is 
as important an agent in preserving fineness of texture and 
mellowness, flexibility and toughness of leather when finished. 

While we practice bating for sheep, goat, calf, kip, and cow 
or yearling, for producing a soft pliable leather, we do not as a 
rule use bates for sole leathers, which are required to be firm 
and solid ; these are generally only washed or rinsed from the 
lime and lightly scudded, then put into the handlers and moved 
till they are colored, souring the liquors and making them 
worse than useless. We would advise puring these from lime 
also, though in a different degree than for light dressing or 
dyeing goods, and the leather though not harsh would be firm, 
tough, and would not grind away like that in which a large 
quantity of lime remained ; the weight also would be improved, 
for the antagonism between the alkali lime and the tannic acid 
when they first come in contact, results in the decomposition 
of gelatine, until the alkaline properties are overcome. 

Not being able to get colors right in glove leathers is gen- 
erally due to poor bating; lime is the great enemy. When 
skins are pickled a chemical change takes place, the lime put 



BATING. 163 

in the skin being changed to sulphate of lime by the sulphuric 
acid, and this clogs the pores of the skin so that no tan liquor 
can get in, but the lime can work out and act upon the colors. 
Sulphate of lime is not soluble in water. It is soluble in lactic 
acid, and it is for this reason that tanners who use sour liquors 
have no trouble with lime, as the sour liquor contains lactic 
acid. Lime left in is sure to produce hard, brittle leather. 
On the other hand bating must be done with care. 

Among the many ways of earning a livelihood is that of col- 
lector of dog-pure, an individual frequently to be met with in 
the tannery districts of Paris, where he goes to dispose of his 
ware. 

In common with the excrements of other carnivorous ani- 
mals, that of the dog contains an acid, which, it is claimed, has 
hitherto defied artificial production, and has the property of 
" cutting " the grease and fat adhering to fresh skins ; it also 
softens and bleaches the skin, and first quality dog-pure is 
valued above all other dung for the reason that the acid it con- 
tains is just powerful enough to produce these results without 
injuring the delicate fibre of the skin. Dog-pure is used by 
manufacturers of fine sheep leathers, especially those making 
leathers for covering corset steels or for purse-linings, and 
many of these establishments are said to have their regular 
salaried collectors. 

The pure is prepared for use by dissolving in water main- 
tained at a temperature of 5 to io° C. for several weeks. 
When " ripe," the " preserves," as the appetizing mixture is 
technically termed in France, is " skimmed," that is, the 
" cream " removed for use, the residue consisting of small 
bones and other detritus, which dogs have an unfortunate habit 
of swallowing, and which would be apt to injure the skins. 
The latter are then placed to soak in the decoction, where they 
acquire that velvety softness so much appreciated. 

The theory of dung bating, while obscure, is that a chemical 
combination is formed with lime under the influence of the 
agents of which the droppings are composed, the ammoniacal 



1 64 THE MANUFACTURE OF LEATHER. 

chloride parting with its chlorine to form the chloride of lime, 
which is readily dissolved in water. 

Hydrochloric acid possesses the property of dissolving lime 
in the manner accomplished by the bate, as was shown by 
MacBride in 1774. 

Carbonate of ammonia was employed by Warrington in 1841, 
for accomplishing the purposes of the bate. 

In addition to the substances named, carbolic acid, sulphuric 
acid, dilute phosphoric acid, organic acids, muriate of ammonia, 
alum, etc., are employed. 

Some of the objections to the present method of bating in 
addition to its expensiveness are: — - 

1. The disagreeable odor and uncleanliness attendant upon 
the use of the excrement of animals. 

2. The difficulty in obtaining properly skilled labor to super- 
intend the operation, which is necessary because of the tendency 
to decomposition produced by the use of animal excrements. 
This decomposition is designated by tanners generally as " run- 
ning away," and means literally that the skins are frequently 
decomposed into a state of liquid putridity, and only skilled 
tanners by watching the vats can detect the approach of such a 
condition. 

3. Then there is such great difference in the strength of the 
same kind of animal excrements, as that of dogs for instance (due 
to the different varieties of food upon which they have been fed, 
vegetables, bones, etc.), that practically no definite period can 
be positively set within which it is safe to let the excrement 
operate. 

4. The influence which the electrical condition of the atmo- 
sphere has upon stock in the bate, which is frequently damaged 
or spoiled during thunder-storms. 

The bating is usually accomplished by placing the hides or 
skins in a vat having a circular and tight bottom, over which 
vat is arranged a revolving paddle wheel marked I in Fig. 35, 
which dips into the solution contained in the vat, thereby agitat- 
ing it and maintaining the sides or skins in constant motion, 



1 66 THE MANUFACTURE OF LEATHER. 

thus hastening the work of bating and greatly lessening the 
time and danger of spoiling the material in the bate. 

After the sides or skins have been properly treated they are 
placed in the interior of the wheel or drum, marked 2 in Fig. 
35, and washed with clear water for a few minutes. 

The English wheels used for agitating the bate liquor, and 
the wheel used for washing the sides or skins, are shown in per- 
spective view in Fig. 35. 

When the sides show the right condition scouring is proceeded 
with, this operation being effected either by hand or by a hide- 
working machine, or the scouring may be performed by the 
Vaughn, Whitney or other macnines shown in Figs. 28 to 34, 
at the time of unhairing and fleshing, if the latter operations be 
performed by machinery. 

The object of this scouring, which should not be confounded 
with the scouring which is to be hereafter described for remov- 
ing the bloom from the hides after tanning, is to free the hides 
from lime and dirt and fit them for the reception of the tannin 
ooze to which they are first subjected in the handlers. 

In the preparation of sole leather the hides are scraped on the 
grain side with a curved knife in order to cleanse them from 
lime remaining in the pores after the last soaking, and this 
operation is termed " graining." 

FINAL SOAKING BEFORE PLACING THE HIDES IN THE OOZE. 

After treating the hides and skins in the above manner, and 
being assured by the previously described tests that they have 
been sufficiently soaked, it is only necessary to replace them in 
water for 5 to 12 hours longer. The safest indication of the 
hides and skins being ready for the ooze is that, when passing 
the fingers over them, strokes remain as indentations. 



CHAPTER X. 



HANDLING AND PLUMPING. 



HANDLING. 

The occasional removal of hides or sides from the vat, and 
then replacing them, also the agitation of the stock at stated 
times while remaining in the liquor in the vat, is termed " hand- 
ling," the object of which is to equalize the action of the lime 
in the unhairing process, the bate in the bating process, and of 
the weak liquor or ooze in the first stage of tanning. 

The old manner of handling hides, like most of the primitive 
methods of the tanner's art, was exceedingly slow as well as 
laborious ; but of late years numerous appliances have been per- 
fected for mechanically performing this work, by means of which 
the stock is handled with great facility and at the expenditure 
of but little labor. One old method was to haul up the sides by 
hand from the vat and pile them, and in this condition, allow 
them to press and drain, and then after a sufficient time throw 
them again into the vat. 

Another and later method was to " shift " or change the sides 
from one vat over into another by means of hooks. 

Handling and transferring the sides by the medium of a 
revolving device, such as the reel, is an old-fashioned method 
which has not yet become obsolete ; but which continues to be 
employed in the majority of both small and large tanneries in 
this country ; in large tanneries the reel being operated by 
power. 

This manner of handling seems to be both convenient and 
economical, and as there are but few objections that can be 
urged against it, there are at present but slight chances of it 
being generally abandoned for later processes, of which we have 
a great variety. 

(167) 



1 68 THE MANUFACTURE OF LEATHER. 

There are two modes in vogue of connecting the sides, which 
are to be handled, with the reel. One is to tie them together 
with strings and the other is to connect them with a tie-loop ; 
but the first method is most commonly employed, and is the 
least expensive. 

The hand-reel is about three feet high, and is made as light 
as possible, consistent with requisite strength, in order that it 
may be readily moved by two men from one vat to another. 

When in use the reel is placed on the alleys intermediately 
between the two vats in which the hides are to be handled, and 
the sides or hides are drawn over the drum by the workman 
who turns the crank attached to the shaft on which the drum is 
fastened. Two men are required to operate this reel, one to 
adjust the sides or hides in the head vat, and the other to work 
the crank. 

Another form of handler in use is known as the rocker 
handler, and it consists of a frame constructed of wood, and 
hung by pivots in the centre of the top of the vat so as to give 
a dipping movement of 7 or 8 in. to each end of the frame, and 
the sides are hung over sticks placed across the frame from the 
two sides, motion being usually imparted to the handler from 
shafting placed overhead. 

The apparatus shown in Figs. 36 and 37 was invented by L. 
C. England, in 1871, and consists in a good method of keeping 
the stock suspended in the liquor, so that all parts may be 
brought into constant contact with the ooze, and its employ- 
ment in liming, bating and handling should produce a smooth 
grain and good quality of leather. 

Fig. 36 is a perspective view of the apparatus, showing it 
removed from the vat. Fig. 37 is a vertical section of the same, 
showing it applied to a tan-vat. 

The frame F is made to conform to the interior of the vat, » 
and consists of the upper and lower rails, 5, S 1 , S 2 , and S 3 , and 
the cross rails E, E 1 , E z , and E 3 , which are joined together by 
means of the uprights U, U 1 , U 2 , U 3 , and £A, and which uprights 
serve as guides to retain the frame in a horizontal position. 



HANDLING AND PLUMBING. 



169 



The frame F is also provided near the lower part with two 
diagonal braces, B, B 1 , at the point of intersection of which is 
an upright shaft R, to which power is applied to operate the 
frame, the braces serving to agitate the liquors. 




Fig. 37. 




The series of bars d d d, are held by the binders T, T z , which 
prevent them from shifting as the frame moves downward. 



170 THE MANUFACTURE OF LEATHER. 

The stock is hung on the movable bars d d d with head and 
butt down, and the proper liquors supplied. 

The frame is placed in the vat so that the top of the stock 
resting on the bars may be about eight or ten inches, more or 
less, below the surface of the liquors. 

The whole frame is then caused to move upward in a vertical 
line of a few inches, four to six being sufficient, but should not 
be allowed to raise the stock above the surface of the liquor. 
The stock being loose on the bars will, when the frame moves 
downward, be left suspended in the liquor, entirely free from 
contact with the bars, thus allowing the liquor free access to 
the parts of the stock, which, when the frame is at rest, adheres 
to the bars on which it is placed. The upward and downward 
vertical motion given to the frame will keep the stock at nearly 
the highest point to which it is raised by the first stroke of the 
frame upward, the frame being moved faster than the stock 
would sink in the liquor if unobstructed. Every returning 
upward stroke of the frame will carry the stock back to the 
highest point again. The frame is caused to move only so fast 
as will have the desired effect, and at intervals, as occasions 
may suggest. 

The specific gravity of the frame and stock being very small, 
the power required to give the necessary motion while they 
are submerged in the liquor is correspondingly small. 

The paddle wheels for handling shown in Chapter IX., Fig. 
35, which were also invented by L. C. England, in 1867, 
are largely employed in handling heavy, medium, and light 
leathers. 

These wheels work within three-quarters of an inch of the 
sides and are usually five and a half feet in diameter, and have 
eleven paddles about seven eighths of an inch thick, and spaced 
equidistant apart, which is about eighteen inches between 
centres at the outer edge. 

The vats in which the wheels revolve have the bottom con- 
cave to conform to the convexity of the wheels which are placed 
over the centre of the vats, so that the wheels dip about eight 



HANDLING AND PLUMBING. 171 

inches in the liquor, and thereby cause a gentle but thorough 
agitation of the ooze and stock, which moves in an opposite 
direction from that of the wheels. 

The motion of the wheels causes the stock to move up in 
front, pass under the wheels, and down on the concave bottom 
to the back of the vat, and thus by means of the paddles, and 
the constant changing position of the stock,' a thorough and 
gentle agitation is maintained. But if the bottom of the vat 
should be made square, the agitation would be too great to 
answer the purpose. 

No fixed length of time can be set for running these wheels, 
as the period depends upon the stock being handled ; light 
sides, as those used for upper leather, being handled for a 
shorter period and not so often as the heavy whole hides em- 
ployed for making enameled and patent leathers. 

The wheel, should for no class of leather be run at a greater 
speed than eighteen revolutions to the minute, and the motion 
should be steady and regular. Cog-gearing is best, and pos- 
sesses a great advantage over belting, as the latter, from the 
slow motion required, often becomes troublesome. 

Wheels of this kind are generally arranged in a line, as shown 
in Fig. 35, and sometimes so constructed that any one of them 
can be thrown out of gear, by means of a clutch connected with 
the loose pinion on the shaft. 

It has at times been tried to apply these wheels to quicken 
the after-process of tanning ; but while they answer for light 
leathers, it is the opinion of some who have experimented with 
them upon heavy leathers that they will not answer; but not- 
withstanding this opinion, we have seen them successfully em- 
ployed at Newark, N. J., and other places, for tanning heavy 
whole hides to be used in the manufacture of enameled leather. 

This wheel furnishes a most simple and effectual mode of 
moving the incipient leather in the liquor, and does away en- 
tirely with the necessity of handling by hand, facilitates the 
after-process of tanning, economizes in labor, forms a hand- 
some grain, and in all respects improves the quality and texture 
of the leather. 



172 THE MANUFACTURE OF LEATHER. 

Methods of handling, such as lacing it together and drawing" 
the stock through rollers, or placing the hides, sides, or skins 
upon a web, unlaced and feeding the stock to the rollers, are 
not now employed in this country. However, they continue to 
be profitably used for some classes of leathers by a few Euro- 
pean tanners, the theory being that by pressing the liquor out 
of the pores in handling upon re-immersion, the liquor into 
which the stock is placed acts more quickly and in the end 
produces a heavier weight than is ordinarily obtained. 

In the manufacture of grain and split leathers the sides are 
tacked upon sticks and handled into stronger liquor about every 
three days, and it might here be stated that any method of 
handling which allows both the grain and flesh sides to be uni- 
formly exposed to the action of the liquor will fill all the re- 
quirements, provided there is a gentle agitation of the fibre at 
occasional periods. 

In some portions of the country the handling is performed by 
placing the stock in the interior of a large revolving drum 
about 10 feet in diameter, one-half of which turns in the liquor 
of the vat, the centre shaft upon which the drum is supported 
turning in bearings resting upon the top of the vat. 

The interiors of these drums are best divided into three or 
four compartments, as it is easier upon the green stock than 
allowing it to be treated in an unpartitioned wheel, and besides 
the operation of the contrivance is facilitated by retaining a 
portion of the contents near the centre. 

In Gorsline's apparatus for handling, the sides or skins are 
placed in the vat resting upon five straps, having cross slats 
attached to them, and one end of each of the straps is attached 
to the top of the vat, and when it is desired to raise the pack, 
the centre strap is wound around a drum which gradually raises 
it, and as it approaches the top, the operator standing upon the 
alley can easily seize the hides and throw them out. 

The slats slide over the centre strap which winds upon the 
drum, thus preventing them from striking the frame and stop- 
ping the machine. 



HANDLING AND PLUMPING. 1 73 

In raising the pack the inclined position it assumes has a 
tendency to wash off the sediment or bloom, presenting the 
same advantage in this respect as in handling by hook in the 
ordinary way. 

This contrivance is better adapted for handling kips and 
skins than for heavy sides or hides. 

PLUMPING. 

The swelling or " plumping" follows the unhairing and flesh- 
ing, and after the bating of the hides, which has been described, 
and it consists of a more or less prolonged immersion in an acid 
liquor, which is gradually increased in strength. Its essential 
action consists in completing the swelling of the cells, distend- 
ing the pores, and thus favoring the absorption of the tannin. 
A secondary action takes place ; it is a commencement of tan*- 
ning due to the presence of a certain quantity of tannin in the 
liquor ; the swelling being due to the action of acetic acid, and 
of the lactic acid. Both acids are products of decomposition 
and oxidation of the non-tannins, such as sugars, gums, etc. 

Some wood vinegar may be added to the sour tan liquor in 
order to accelerate the swelling. This process does not cause 
any damage to the quality of the leather ; but some tanners 
replace the acetic acid by sulphuric acid, which, at an equal 
degree of acidity, costs considerably less. This practice is 
prejudicial to the quality of the leather. It is true that the 
swelling is satisfactorily produced, and the leather looks well, 
but, prepared in this manner, it retains traces of sulphuric acid 
which corrode it internally after a time, and make it very 
brittle and more subject to alteration by moisture, and there are 
other defects which will be mentioned shortly. 

The " plumping" process is applied to the heavier classes of 
hides only, such as those employed for the manufacture of sole- 
leather, upper-leather, harness, belting, patent and enamel 
leathers, etc. 

PLUMPING BY MEANS OF SOUR LIQUOR. 

There are at present two methods in common use by which 



174 THE MANUFACTURE OF LEATHER. 

this plumping is accomplished, as has been stated, In one of 
these the tanning-liquor which has been in use for some time, 
is made use of under the name of "tailings," or sour liquor, in 
which the hide having been properly prepared is first placed. 

The fresh tan-liquors after a short time become changed in 
their character and nature, and the resultant is a liquid in which 
we find tannic, gallic, and acetic acids in varying proportions, 
combined with decaying vegetable and putrescent animal mat- 
ter; but the presence of the latter substances seriously interferes 
with the exhibition of those active principles which the tanner 
seeks to utilize from his sour liquors, and it is the presence of 
this decomposed matter that forms the only objection to this 
method of plumping hides, and from which the principal dan- 
ger arises, which, while not great, still requires watchfulness. 

The second method of plumping, which will be enlarged 
upon in the next section of this chapter, is to steep the hides in 
a cold, dilute sulphuric-acid liquor. 

But while the latter method expedites the work, it has the 
effect of rendering the leather harsh, liable to be brittle, and 
gives a dark grain to the same, it being conceded by all practi- 
cal tanners that the process in which the plumping is wrought 
by the presence of the acetic acid in the tailings is far prefera- 
ble, could the same be divested of the trouble arising from the 
decaying animal and vegetable substances present in all tan- 
ning liquors which have been used for any length of time. 

H. J. Botchford, of Leyden, N. Y., proposes to remedy this 
by subjecting the sour liquors to a distillation in a still suitably 
constructed, by which the acetic and other volatile acids are 
recovered in a pure form, freed from the other substances of 
the liquors. The distillate thus resulting is now taken, and, in 
a properly dilute form, is again used as a liquid in which the 
plumping of the hides may be very expeditiously and satisfac- 
torily accomplished. 

In the practical working of this process the distillation is 
best accomplished by the use of a still in which the liquors 
from which the acid products are to be recovered are heated 



HANDLING AND PLUMPING. 175 

by means of a steam-worm coiled within the body of the retort 
containing the said liquors, the vapors of the acids thus liber- 
ated being conducted from the head of the retort through a 
tubular condenser, the temperature of which is maintained at a 
sufficiently low point for the proper condensation of the acid 
vapors by surrounding the same with water at a low degree of 
heat; but any apparatus ordinarily termed a "still" will an- 
swer, as long as its materials are arranged to be proof against 
the attack of the acids to be recovered, and the heat of which 
can be maintained equally. 

PLUMPING BY MEANS OF SULPHURIC ACID. 

In 1773, David MacBride, a physician of Dublin, introduced 
the employment of sulphuric acid for swelling or plumping 
hides, and though it may appear strange that such an improve- 
ment should have been made by a member of the medical pro- 
fession, still this, like many other advances, was the result of 
accident, which arose from a series of experiments carried on 
for purely medical purposes, for confirming a theory that an 
infusion of malt would cure the sea-scurvy. 

MacBride for four years kept the matter a partial secret, im- 
parting the knowledge to only one firm of tanners in the city 
of Dublin; but on May 31, 1777, after being at liberty to dis- 
close it, he did so in a communication to the Royal Society, and 
it is recorded among the Philosophical Transactions. 

Sulphuric acid or vitriol, as it is also termed, is used for 
plumping both lime and sweat stock. The coloring and plump- 
ing of the latter are usually accomplished simultaneously in the 
handlers, the liquor being strengthened after the removal of 
each pack. 

But while vitriol can be employed without danger on limed 
stock, it is desirable to observe caution in employing it upon 
sweat stock in order that it may not be too much swelled, as 
its action is more energetic upon hides which have been sub- 
jected to the sweating process. 

Some tanners find that it is an improvement to treat sweated 



176 THE MANUFACTURE OF LEATHER.. 

hides to a weak lime bath, especially when they are to be 
plumped by sulphuric acid. 

The acid is diluted with cold water, and sometimes more or 
less of the old sour tan liquors are employed in conjunction 
with the sulphuric acid, in order to hasten the process of pre- 
paring the hides for the tanning proper. 

It is, of course, impossible to give the exact proportion of 
vitriol to be employed in every case ; but the quantity now 
used is about the same as that prescribed by MacBride, more 
than a century ago, viz., to use his own language, " a wine 
pint of the strong spirit of vitriol is sufficient for fifty gallons of 
water to prepare the souring at first; therefore, all you have 
to do in raising sole leather, is only to prepare it beforehand 
in the usual way, and when it is fitted for the souring, mix up 
a quantity of vitriol and water, according to the number of 
hides that you require to have raised, still observing the pro- 
portion of a pint to fifty gallons, which will be enough if the 
vitriol be of the due degree of strength. The hides may lie in 
the souring till you find them sufficiently raised, for they will 
be in no danger of rotting, as they would be in the common 
sourings, which in time might turn putrid and rot the leather, 
whereas the vitriolic liquid keeps off putrefaction." 

In the early use of sulphuric acid by our tanners, an almost 
general lack of knowledge of the nature and effect of sul- 
phuric acid under certain conditions was largely prevalent, and 
much harm resulted from its injudicious employment in the 
handlers ; but while practical experience has done much to aid 
the tanner in obviating disastrous results, there is still much 
desirable knowledge regarding its use in tanning that can re- 
sult only from chemical experiments. 

The most concentrated sulphuric acid is a definite combina- 
tion of forty parts sulphuric oxide and nine parts of water, the 
formulas representing it being H a O, S0 3 , or H 2 S0 and it is a 
colorless oily liquid having a specific gravity of about 1. 85, of 
intensely acid taste and reaction. 

Oil of vitriol has a most energetic attraction for water, it 



HANDLING AND PLUMPING. 177 

withdraws aqueous vapor from the air, and when it is diluted 
with water great heat is evolved, so that the mixture requires 
to be made with caution. 

The atmosphere is invariably charged with moisture, some- 
times to the point of extreme dampness and complete satura- 
tion, while at other times it is considerably above the point of 
saturation. Any raw material, therefore, which is exposed to 
the atmosphere absorbs to a greater or less degree a certain 
quantity of water. Some chemicals absorb a large percentage 
and are on this account called hygroscopic. 

For example, ordinary sulphuric acid or oil of vitriol has a 
great affinity for water, and a glass half full of acid, will, if 
exposed, gradually fill up and overflow with water, added by 
the mere attraction of moisture from the atmosphere. Sul- 
phuric acid is an extremely hygroscopic substance, the mois- 
ture absorbed being considerably over ioo per cent. 

The specific gravity of sulphuric acid being so much greater 
than tan-liquor, it has at all times a strong tendency to settle 
and mark with spots of different colors the grain of the pack, 
and is is only by strict watchfulness that this can be avoided, 
and when vitriol is added to the pack, it should be done before 
the sides are thrown in, and the plunging should be faithfully 
performed in order to prevent the discoloring of the grain by 
the settling of the acid. The swelling or " plumping" process 
is, for the reasons previously stated, accelerated, and the falling 
back of the hides into their previous state prevented by the use 
of hard water. 

PLUMPING BY MEANS OF ACETIC ACID. 

The most experienced tanners do not consider the use of 
acetic acid as advantageous for swelling sole leather. While it 
is admitted that the acid will make the cellular substance of 
the hide absorb water and thus swell, and will also prepare the 
gelatines of the hide for the further processes of tanning, but 
the acid will destroy the albumen and the albumen cells of the 
hide. For this reason, hides tanned in old acid liquors are 
12 



178 THE MANUFACTURE OF LEATHER. 

always weaker, soft and spongy. Mineral acids are still more 
destructive, as they coagulate the albumen of the hide and give 
it a brittleness, while they also attack other constituents of the 
hide and prevent the natural fermentation of the liquors. If 
sole leathers in the first liquors are swelled by the use of min- 
eral acids, the albumens cannot come to the surface of the hide. 
The gelatines will be dissolved, but according to the strength 
of acid used will be more or less decomposed, and the result 
will be that the finished leather will look bad as to color, but 
will be hard and liable to crack. Fir tannins are supposed to 
contain more acid-swelling properties than either mineral or 
acetic acid, and German tanners add it to their liquors and 
allow it to ferment for this purpose. This is considered the 
only proper means of swelling hides without injury to the 
cellular tissues or the destruction or displacement of the al- 
bumen of the hide. Lactic acid is a good agent for plumping 
hides — the only objection to it being its present high cost. 



CHAPTER XI. 

LAYING-AWAY. 

The hides having been raised, the texture dilated, and there- 
fore weakened, and being deprived of that natural gum which 
absorbs moisture, are in a condition to be tanned, that is to 
have their fibres strengthened and re-united. 

Tannin is, therefore, an astringent and impregnating substance, 
by the ageney of which the fibres maintain their independence 
and the faculty, as it were, of sliding one upon another in their 
moist state, and by the means of which, also, the dried leather 
is rendered manageable and elastic. 

Without tannin the skin becomes horny as it dries, and loses 
all elasticity and malleability, which is due to the fact that the 
bunches of interwoven and compact fibrous cellular tissue, of 
which it is composed, stick together, and constitute then a con- 
tinuous, semi-transparent mass. 

Leather is probably not, as has been heretofore considered, a 
chemical combination of the animal substance with the tanning 
substance; for the reason that the latter* is never absorbed in 
equal proportions, but in variable quantities, according to the 
concentration of the liquid and the nature of the dissolvent. 
" One may even obtain leather by the sole use of fatty sub- 
stances, for which there can be no question of a chemical com- 
bination with the animal tissue. Mr. Knapp has even suc- 
ceeded in tanning or making leather without tanning elements. 

* Some chemists object to this paragraph, one writing as follows : " It cannot be 
said that for the reason the tanning substance is never absorbed, etc., because a piece 
of leather which is thoroughly tanned, when shredded and treated with petroleum 
naphtha to remove fat, oil and water, and to thoroughly remove all soluble matter, 
such as tannin and non-tannins, always contains about the same amount of hide 
substance and tanning substance after deducting the mineral matter or ash." 

fi79) 



l8o THE MANUFACTURE OF LEATHER. 

Starting from this principle that the filaments adhere or stick 
together only when they are swollen by water, he has put the 
hide in contact with such a liquid as alcohol or ether, which, 
expelling the water by endosmosis, deprives the fibres of their 
faculty of sticking. He has obtained in this way a tawed skin, 
of a nice white color, and having all the physical qualities of 
tawed hides. The same result is obtained by suspending a 
cleansed skin in anhydrous ether placed above a layer of chlor- 
ide of calcium. The water with which it is impregnated diffuses 
itself in the ether and is gradually absorbed by the chloride of 
calcium. Any leather thus prepared — the only difference in 
which from the moist hide, dried and horny, consists in the 
physical state of the fibres, which have kept their independence 
— becomes an ordinary skin, with all its qualities, as soon as it 
is moistened. 

" It results from these interesting experiments that tanning is 
based rather on a physical action than on a chemical reaction. 
The tanning substances, penetrating the hide by endosmosis, 
envelop the fibres, adhere on their surface through an attrac- 
tion similar to that which causes the precipitation of coloring 
matters on the surface of textile fibres. The fibres thus sur- 
rounded by a layer of foreign matter do not adhere any more 
in drying. 

"The faculty which the tanning substances possess besides, 
of rendering the leather imputrescible, is independent of their 
physical action. It may disclose itself more or less energeti- 
cally, according to the more or less antiseptic nature of the 
compound used. 

" A very interesting experiment of Knapp shows besides that 
one may compare the leathers, as regards the solidity of the 
tanning with dyed tissues, some of which are of good tint and 
others of false tint. 

"Thus the hides tanned with tan-bark resist the action of 
water, while those prepared with the tannin of the gall-nut 
come back to the state of untanned hide, after a prolonged 
wash with carbonate of soda, which proves that the active 



LAYING- AW AY. I 8 I 

substance of tan is not entirely identical with gallotannic 
acid." * 

Following this theoretic discussion we shall now proceed 
with the final step in the process of tanning heavy hides and 
skins, such as are employed for sole and upper leathers, etc., 
which is the laying away of the stock. The usual size of the 
lay-away vats for sole leather hides is nine feet long, seven feet 
wide and eight feet deep, and in these the stock is usually 
placed with the grain side up in order to avoid " hook marks " 
in removing them. 

The stock is laid away by being spread out smoothly and 
upon the bottom of the tanvat, and between each layer there 
is sprinkled a slight thickness of ground bark until the vat is 
filled by the stock and bark thus laid in stratum super stratum. 

Tan-liquor is then run into the vat, and when the interstices 
are filled the whole is crowned with a layer of bark which tan- 
ners call a "heading." 

Formerly the inter-laying layers of bark were depended upon 
to do the tanning ; but at the present time in this country the 
bark-liquor is relied upon and not the inter-laying bark. 

The bark ought not to be shaved too fine for the lay-aways. 
This is important where whole hides are tanned. It is not so 
important where sides are tanned. If the bark is too fine, it 
excludes the liquor from circulation between the hides, and 
they do not come out of the lay-aways fully tanned. 

In the early stages the green stock requires more attention 
than when it is nearly tanned, as at first it absorbs the tannin 
very rapidly and then gradually its capacity for absorption 
grows less until at the finish it refuses further to imbibe the 
tannic acid. The skins do not absorb an unlimited quantity of 
tannin, and are probably not improved by remaining a long 
time in the vat. 

The number of layers and the period of each differ for the 
various leathers, and depend upon the substance and weight of 

*Wurtz. Dictionnaire de Chimie, Pure et Appliquee, iii., 193 et seq. 



1 82 THE MANUFACTURE OF LEATHER. 

the stock, the strength of the liquors to which it is subjected, 
the season of the year and various other appendant matters ; 
but it is not uncommon in this country to tan the heaviest sole- 
leather in four layers of the following periods, the liquors at the 
end of each stage being of the indicated degrees of strength, 
which gradually increase from say 6° at the start, to about 30 
at the finish : 

1st layer, 12 days . . . . .15° 

2d " 18 " 20 

3d " 24 " 25 

•Jth " 36 " ' 30 

Making the whole period ninety days, and in some cases it 
has been accomplished in much less time. See Chapter XXIV. 

In order to obtain full weight and brighter color the time of 
the final layer is prolonged, for when insufficient time is allowed 
to this layer there will be lack of solidity and the grains will be 
inferior. 

In the manufacture of finer grades, such as oak-tanned 
sole-leather of the kind which is used for the soles of ladies' and 
children's shoes, the packs are generally laid away five times. 
New liquors, or mixtures of new and old, are preferable for dry 
hides, old liquors for slaughtered. When laid-away in bark 
the packs are changed, as has been stated, until tanned. Much 
care and judgment are necessary in proportioning the continu- 
ally increasing strength of the liquors to the requirements of 
the leather in the different stages of the process. The liquors 
should also be kept as cool as possible, within certain limits, 
and ought never to exceed a temperature of 8o° F. Too high 
a heat, with a liquor strongly charged with the tanning princi- 
ple, is injurious to the life and color of the leather, and the use 
of a too weak one must also be avoided. Hides treated with 
liquors below the proper strength become relaxed in their tex- 
ture and lose a portion of their gelatine. The leather loses in 
weight, and is much more porous. The greatest strength of 



LAVING-AWAV. 



183 



liquor used for handling should not exceed 16 by the barko- 
meter : and that employed in laying-away should mark at its 
greatest strength from 30 to 35 . 

It is the custom, when the liquors in the lay-away vats are 
gradually increased in strength, to remove the packs after the 
stock has laid-away long enough, and run the ooze through 
wooden pipes into a receiver, and from thence to pump the 
liquor back to the leaches, where it passes through the bark and 
is restrengthened, and then run as new liquor into the vats. 

Another methcd is to allow the fresh and strongest liquor 
direct from the leaches to pass first upon the head packs of the 
last layer, and from thence to the next, and so on through all 
the layers, and of course decreasing in strength and becoming 
more acid until it finally passes upon the first lay-aways, or 
into the handlers, where it is exhausted. 

When this method is employed the liquors when they come 
from the leaches should be at least 30 and ought not to exceed 
35 in strength; but the liquor should never in the end be 
allowed to remain upon the stock after the strength is spent. 

When heat is used on the head leaches the liquor sometimes 
enters the lay-away yard in a hot condition, and the intent is of 
course to turn it into the head lay-away ; but sometimes the 
attendant by mistake allows it to run on the green stock, thereby 
causing damage to the leather, as the " black rot" will be cer- 
tain to set in to greater or less extent, especially in the heated 
season of the year. 

Fig. 38. 




The jack shown in Fig. 38 is used for raising whole hides up 
in the lay- away vats so that the men can take hold of them. 



1 84 THE MANUFACTURE OF LEATHER. 

When the whole hides are laid away, they are placed upon a 
float made by floating two sticks about two inches square length- 
wise of the vat on top of the liquor, and then lowering a piece 
of timber 4x6 inches so that it will be in the centre of the vat 
at right angles to the length. This timber has a hole through 
each end, through which passes a rope which is long enough 
to extend about two feet above the top of the vat. Two short 
sticks are then laid across the two long sticks near the ends, 
and the hides are then laid away in the usual manner. 

As laying away continues, the float sinks. When the time 
comes to raise the hides, a jack is placed alongside the vat and 
the end of the rope wrapped around the hook on the end of 
the jack, and the hides are gradually lifted to the full extent of 
the jack, and the rope is wrapped around a movable peg, which 
is placed in a hole 1 yi inches from the edge of the vat in the 
alley or partition which separates the vats. Then the jack is 
carried to the opposite side of the vat, where the operation is 
repeated. 

In tanning heavy upper leather the practice among some of 
our best tanners is to first handle the sides on sticks for ten or 
twelve days, and then lay them away twice in bark, both lay- 
aways generally extending over a period of about sixty days, 
the first lay-away being for about twelve days and the second 
for about forty-eight days. After this the sides are split and 
then, after being leveled off, the sides, twenty-five at one time, 
are placed in a large revolving wheel and worked for about ten 
minutes with moderately strong gambier liquor. From thence 
the sides go again into the handlers, but this time without 
sticks, and are drawn each day for about fifteen days. This 
completes the tanning of the upper leather, and it is then ready 
for the scouring and finishing. 

Light upper leather, such as grain and splits, is not laid away. 



CHAPTER XII. 

STONING. 

PREVIOUS to splitting, leather is usually "stoned out" to 
remove the wrinkles in the sides. This is best done with a 
stoning jack. 

Fig. 39 shows the stoning jack made by J. T. Freeman & 
Co., Woburn, Mass., and it is one of the best machines made 
for the purpose. 

Fig. 39. 



STONING JACK. 

This is a very strong jack, and is especially constructed for 
stoning out rough leather preparatory to splitting. It will 
stand a very heavy pressure and is just the machine to take 
out the wrinkle in rough harness or belt leather, etc. 

The Vaughn machine shown in Chapter XVI is also invalu- 
able for stoning out previous to splitting. 

( 185 ) 



CHAPTER XIII. 



SPLITTING LEATHER. 



After the sides have been removed from the handler vats 
they are — in the manufacture of upper leather and some other 
varieties of leather — hung on poles in the yard of the tannery 
to harden, or pressed in a power press sufficiently dry for the 
splitting machine, and then carried to the cellar preparatory to 
being split. For other and more minute details in relation to 
splitting leather the reader is referred to the chapters treating 
of the manufacture of grain and split leathers. 

Fig. 40 shows an interior peispective view of the cellar of an 
upper-leather tannery. Piles of sides that have been dam- 
pened, and in condition to be split are shown at 1 and 4. The 
three splitting machines in a line, marked 2, are known as the 
Union Splitting Machines ; the one in the background marked 
3, is the Belt-Knife Machine. The manner in which power is 
supplied to the machines by means of a line-shaft is shown, the 
line-shaft being marked 5. 

For those who are building or equipping tanneries, views of 
this kind contain many valuable suggestions, as those in this 
work were taken under the author's personal supervision from 
some of the most modern and concededly the best arranged 
tanneries in the United States. 

SPLITTING MACHINES. 

Early in 1831 Alpha Richardson, of Boston, Mass., patented 
his first splitting machine for leather. 

Seth Boyden, of Newark, N. J., had nearly a quarter of a 
century previous to this invented a machine for this purpose ; 
but while a large number of machines of this character had 

(186) 



SPLITTING LEATHER. 



18; 




1 88 THE MANUFACTURE OF LEATHER. 

come into use, there were numerous objections to them which 
it remained for Richardson to overcome. 

He gave great attention to the perfection of his contrivance,, 
and continued to improve it until 1856, when he combined all 
his patents in the " Union Splitting Machine." 

Since the successful introduction of splitting machines hides 
have been split to meet all required conditions, and they may 
be split either in a green or tanned state. 

In the manufacture of heavy upper leather the sides are split 
after being only partially tanned. 

When it is desired to split whole hides, as in the manufacture 
of enameled leather for carriage tops, etc., a machine con- 
structed on a different principle is employed. The one in most 
common use for this purpose is known as the " Belt-Knife 
Splitting Machine," which was invented in 1854 by Joseph F. 
Flanders and Jere A. Marden of Newburyport, Mass., and 
which machine is now manufactured by The American Tool 
and Machine Co., Boston, Mass. The Belt-knife Machine has 
almost driven the Union Splitting Machine out of the eastern 
currying shops, but the latter machine is still employed in the 
western states. 

The facilities afforded by machines of the character that have 
been mentioned, allow good "grain splits" to be obtained, 
which are used very largely for shoes, and also for harness, 
trunks, etc., and the large production of buffed and grain 
leathers, which are now so much used in this country, and form 
an important item in our export list, has been greatly aided by 
them. 

Fig. 41 shows a perspective view of the Union Splitting 
Machine, geared so as to be run by steam power. 

Fig. 42 shows a perspective view of an attachment patented 
in 1883 by John A. Enos, to prevent injury to the arms of those 
who operate the ordinary splitting machines of the character 
which have been described above. 

As generally practiced in the factories where leather-splitting 
is carried on largely, the leather is held pressed against and 



SPLITTING LEATHER. 



189 



wrapped around the drawing-roller by the hands of the opera- 
tor, who is in great danger of being caught and having his arms 
broken, such accidents being of very frequent occurrence. 



Fig. 41. 



® 1 




Machines have also been made in which the leather has been 
drawn or fed against the edge of the knife or cutter by a pair 

Fig. 42. 




-of cylindrical rolls which act upon the opposite surfaces of the 
leather, pinching it between them ; but when a stationary knife 



190 



THE MANUFACTURE OF LEATHER. 



or cutter is employed, it is claimed that it has been found im- 
practicable to use such a pair of feeding-rollers, as their holding 
power is not sufficient to draw the leather uniformly against 
the edge of the cutter. Enos discovered that by fluting or 
corrugating the surfaces of the drawing or feeding rollers, and 
preferably also gearing them together, so that the projections 
or convex portions of one roller will fall within the recesses or 
concave portions of the other roller, it is possible to obtain suf- 
ficient holding power upon the leather to draw it properly 
against the edge of the knife and split the leather. 

Enos's invention is shown in detail in Figs. 43 to 45, and 
consists, essentially, in the combination, with the usual splitting 
knife and parts co-operating therewith, to present the leather 
properly to its edge, of a fluted or corrugated drawing roller 
and a corrugated or fluted auxiliary or gripping roller, and 
mechanism by which the operator can force the rollers against 
the leather between them. 

In the present embodiment of this invention the gripping 
roller is mounted in bearings upon pivoted arms, which are 
acted upon by an actuating-treadle to draw the gripping rolier 

Fig. 43. 




toward the drawing-roller, and the gripping-roller is drawn 
back or retracted by its own weight or other suitable retractor, 



SPLITTING LEATHER. 



191 



so that the operator by merely raising his foot can at once re- 
lieve the pressure on the leather, which will then cease to be 
drawn. 

Fig. 43 is a front elevation of a leather-splitting machine 
embodying Enos's invention ; Fig. 44 an end elevation thereof; 
and Fig. 45 a vertical section on line x x, Fig. 43. 

The framework a, knife b, and mechanism for presenting the 
leather to be split to the knife-edge, may all be of any usual 



Fig. 44. 



Fig. 45. 





construction, these parts not constituting the present invention. 
The leather presented to the knife at a short distance from the 
end of the piece or side has its end carried over the' corrugated 
or fluted drawing- roller e, mounted on a shaft/, shown as actu- 
ated by a gear, g, meshing with a pinion, h, on a shaft, z, hav- 
ing the usual fast and loose pulleys for the driving-belt. Thus 
by wrapping the leather around the roller e, or pressing it 
against the surface thereof, the leather will be drawn against 
the edge of the knife and split by the power by which the 
roller is rotated, although it is necessary, in addition to the 
power, to provide means for holding the leather upon the sur- 
face of the drawing-roller. This is accomplished in accord- 
ance with the present invention by the auxiliary or gripping 
roller m, having its bearings in carrying-arms n, pivoted on the 



192 THE MANUFACTURE OF LEATHER. 

shaft o, so that the roller can be swung or oscillated upon the 
arms toward and from the roller e. The arms n have exten- 
sions n' ', forming therewith a bent actuating-lever for moving 
the roller m toward the roller e, the extensions or arms n' being 
provided with counter-balance weights, w, for partly balancing 
the weight of the roller m. The arms n' are connected by links 
or rods p with the actuating-treadle r, so that the operator, by 
depressing the treadle, forces the roller m toward the roller e to 
grip the leather between them. The roller m is corrugated or 
fluted to correspond with the roller e, as shown in Fig. 45, and 
the roller e is provided at one end with a gear, s, meshing with 
an intermediate t, that meshes with a pinion, t', fixed upon the 
shaft 0, which has at its other end a pinion, u, meshing with a 
gear u', connected with the roller m. The gears s and u' are of 
the same size, and the pinion 1 1" u are of uniform size, so that 
the rollers m and e rotate in unison in opposite directions and 
the projections of the one roller fall into the recesses of the 
other. The two rollers thus co-operate to grip and draw the 
leather, which passes down between the rollers instead of being 
wrapped around one roller, as in the machines heretofore em- 
ployed. By the employment, in connection with a fluted 
drawing-roller actuated by power in the usual manner, of a 
corresponding fluted auxiliary roller — or, in other words, a 
co-operating pair of fluting, gripping, and drawing rollers — the 
danger to the operator, it is claimed, is removed, and the oper- 
ation and capacity of the machine for splitting the leather are 
improved and increased. 

In the old machines employing but a single roller, the 
leather, when wrapped around it, frequently forms bunches, 
causing inequality in the tension of the leather, and consequent 
inequality in the thickness of the split material. 

Frequently difficulty in splitting is traced to simple causes, 
which are easily remedied. Sometimes the hides are not 
properly soaked, and at others the machine is not correctly 
adjusted. The leather should be soaked just enough to allow 
the water to penetrate the hide, and no more. After that it 



SPLITTING LEATHER. 193 

should be allowed to mellow, which should be from twelve to 
twenty-four hours. Care should be taken to cover the edges 
with wet cloths or splits, and to put them in a clean place 
where they will not get grit. In most cases it will be found 
advantageous to soak them in warm water. 

With the Union Splitting Machine the following hints may 
prove valuable : Before putting in the leather to split, turn the 
beam roller over on to the knife, and see if the center of the 
roller sits exactly over the edge of the spring plate, and, if it 
does not, adjust it by moving the two screws, one on each side 
in front of the gauge box ; next see that the edge of the knife is 
slightly below the spring plate, and about the distance of a cent 
piece away ; see that the spring plate is gauged exactly true 
along the edge. To prove this, place the coin on the face of the 
knife, and close up to the spring plate ; run the coin across from 
one side to the other, and, if the plate is not perfectly even and 
square with the edge of the coin all across, regulate the same 
with the long spanner by moving the screws underneath ; if the 
spring plate is not set perfectly true, unevenness of substance 
will be the result. In gauging, first try the machine on a split, 
so that little damage will be done if the exact distance is not 
obtained the first try, also see that the spring plate sits evenly on 
the screws all along ; otherwise, regulate with the eye bolts that 
are underneath. To ascertain if the plate sits on the screws, 
strike the plate lightly with a hammer over the screws, and it 
will be noticed if the plate springs or not ; allow the plates to be 
sprung slightly hollow from back to front. An important point 
to be observed is the proper sharpening of the knife. It is 
almost an impossibility to keep a knife true and the edges in 
good condition by hand sharpening. Care should be taken to 
clear the edges, and for this purpose Scotch or Tarn O'Shanter 
stones are considered the best. After properly fixing the knife, 
place the leather across with the belly part towards the outside, 
and bring down the roller, taking care that the same is properly 
pressed home with the lever before starting the machine. 
When splitting whole sides, assist the belly part through as 
13 



194 THE MANUFACTURE OF LEATHER. 

much as possible by pulling at the edge ; otherwise, the belly 
being longer than the straight edge, the surplus will be worked 
back and puckered up, cutting it in holes. If the sides are in- 
clined to be baggy or pouchy, take the wood from the lip roller 
and place one hand opposite the bag or pouch, and work the 
machine until the pucker is drawn out; then again place the 
wood in lip roller and finish the side. When placing the hands 
on the roller to draw out a pouch, particular care must be 
taken not to allow the hands to get too far underneath round 
the roller, as the fingers are apt to be trapped with the leather, 
and the arm broken or pulled out, which has happened on 
several occasions. 

THE BELT KNIFE LEATHER SPLITTING MACHINE. 

The American Tool and Machine Co., of Boston, are the 
original manufacturers of the belt knife Splitting Machine 
shown in Fig. 46, having been manufacturing them for the last 
thirty years. 

The original machine was developed after the expenditure of 
large sums of money and valuable time, and has been steadily 
improved during the past twenty years, particular attention 
having been paid to alterations and changes in the machine 
during the last three years. Their most recent machine is 
shown in the illustration. 

In view of the fact that the first machines were built to run at 
a speed of about 150 revolutions per minute, its speed has 
gradually increased until now some of the machines are run at 
as high a rate of speed as 425 revolutions. This high speed is 
admissible on some kinds of leather, but for the general split- 
ting work the builders recommend a speed of from 300 to 350 
per minute. 

The necessity and anxiety to do work and do it quickly, in 
order to reduce the cost of production, were not provided for in 
all cases, and the machines were not strengthened and re- 
modeled to meet the high speeds and the most severe work 
demanded by the leather manufacturers until within the last 



SPLITTING LEATHER. 1 95 

three years. Since then the builders have been making con- 
stant improvements and the machine has been practically re- 
modeled, having been made much heavier in all parts that past 
experience had proven required strengthening, and the quality 
of the material of which the machine is made received special 
consideration, so that to-day they are turning out a machine 
that is made of the materials best suited to withstand the severe 
duties demanded. 

This point was one that required long and careful experi- 
menting to determine which material was best suited for the 
service. In many cases seemingly unimportant parts of the 
machine required the most care and experiment before the most 
satisfactory material to use could be determined on. 

The high speeds of the present day require a massive con- 
struction and strength to reduce the vibration and strains, and 
it was found that the ordinary materials that could be pur- 
chased from stock were unsuited, and the American Tool and 
Machine Co. were therefore obliged to have special steel manu- 
factured to suit the purpose. 

The latest machines that have been put into the manufac- 
turers' hands, and run by experienced men who have used these 
machines for the past fifteen or twenty years, have been pro- 
nounced much better, and the fact that the amount of repair 
work has been reduced nearly 75 per cent., indicates that the 
builders have a machine that is economical and exceedingly 
durable. 

We would mention among other things that the builders have 
increased the weight of the machine very materially, thus mak- 
ing it stiffer and stronger. They have put on gears that are 
machine cut; the rolls and shafts are carefully turned; the 
screws are lathe made and are closely fitted. 

These are small points, but the fact that the machine, in 
order to do good work, must be taken down and cared for and 
replaced, necessitates that all the screws and parts should be 
made of material that will stand the handling and the reassem- 
bling without getting out of true, without the threads stretching 
or the holes wearing unduly. 



ig6 



THE MANUFACTURE OF LEATHER. 




When the machine and parts are worn it is difficult to do 
close and good work and keep the knife properly adjusted. 



SPLITTING LEATHER. 1 97 

The position of the knife and the beam and its parts is very 
important to do good work continually, and it is necessary that 
they maintain their adjustment after they are set, as the splitter 
must use up much valuable time and delay on the work by 
continually stopping to adjust his machine. 

The machine is not automatic, and to insure the best work, 
it does not seem practical at this time to manufacture a machine 
that will automatically split leather ; therefore to obtain the 
highest standard of work, it is necessary that a man should have 
experience in handling a machine and must understand some- 
thing about leather in order to make a successful splitter. In 
setting up the machine and adjusting it, and getting out work 
properly, there are many things that will bother a man who is 
not thoroughly familiar with the machine, and it is only by 
careful study and the closest observation that the expert split- 
ters are able and have been able to attain the position they 
hold. It has been very truthfully said by several of the most 
expert, that they have made the machine a careful study, and 
have really made it a life work. 

These men can split anything in the shape of leather or 
material that can be cut with a knife that is required to be 
evened or divided into different thicknesses. There is no class 
of leather that is too difficult to split on the machine under the 
careful handling of the expert man ; leather in all stages of 
manufacture from the raw state to the finished product. 

As will be inferred from the above, it is practically impossible 
for a man to learn the art of splitting leather from any written 
description or written instruction that can be given. 

We might mention that the belt-knife splitting machine is in 
successful operation for splitting pan- cake and counter stock, 
splitting shoe linings, splitting calf, goat and sheep skins, split- 
ting and skiving grain leather, splitting book-binding and bag- 
stock, skiving harness leather and belt butts, splitting felt for 
hats, splitting and buffing leather for carriage tops and enamel 
leather, splitting green hides with hair on for robes and coats, 
splitting hides or skins from the lime ; also celluloid in sheets 
and cow horns for combs. 



198 THE MANUFACTURE OF LEATHER. 

Referring to the matter of grinders, we would say that the 
builders have been experimenting for some time on a new 
form of conveying the power to the grinder shafts, and that 
they will soon have a very simple, inexpensive arrangement, 
which we trust will be appreciated by all who use it. 

It is always necessary on high speed machinery to provide 
a device for stopping and starting the machinery readily, as 
when a machine is running at high speed it is highly important 
that it should be stopped in case anything should become out 
of order, before any damage could be done to it ; for this 
reason, the American Tool and Machine Co. have gotten out a 
new and improved patent friction pulley for the machine, by 
means of which it can be started with less power than the ordi- 
nary shifting belt requires ; that is, the clutch that is provided 
with this pulley, is so constructed that the machine can be 
gradually started and instantly stopped. 

IN REGARD TO SPLITTING LEATHER 

a few instructions may not be amiss. 

Everything being ready, place the leather in two piles behind 
the machine. Place it so the backs, as you pick it up, will 
come against the head blocks, the flanks at the middle ; put the 
heaviest at the bottom, the lightest at the top, for as your knife 
wears away you are feeding larger leather which requires more 
room, you thus avoid resetting the knife so often. Take a side 
of leather, grain up, the hind shank first, the neck hanging 
down and the back hanging straight, lay it upon the ring plate, 
spread it as flat as possible, with one hand push or feed in the 
projecting part of the skin, with the other hand grasp the rib 
on the guard over the main shaft, holding thus the leather from 
feeding too fast. As soon as it begins to feed take the loose end 
and with the hand on the ring plate spread or straighten the 
side out so as to be sure not to let the leather catch at the two 
sides before the middle does, as otherwise the leather will not 
spread evenly, but bunch up in the middle. When that occurs 
you must stop the machine and raise the beam and draw it 



SPLITTING LEATHER. 1 99 

back as far as it is bunched up, and turn down the beam and 
start again. Do not pull all the leather out or you may have 
trouble in starting in true again. When you have the leather 
well fed in, the width of the side, let it go, for the less hindrance 
you put upon the feeding the better the results will be. After 
you have split some twenty-five or thirty sides examine the 
knife, as the wheels are constantly grinding it away. You must 
keep resetting it ; experience alone can tell you how much to 
keep the knife up to or away from the notch, but until you 
have had experience adopt one-eighth of an inch as a safe dis- 
tance ; or rather the nearer you can come and have a scrap of 
leather feed straight through when the machine is set, the bet- 
ter it will be. If the knife is too close the leather will not 
feed through, but will be carried by the knife along the jaw to 
the end. If you should, as is done in this country, skive the 
leather, the operation is the same, except you feed with the 
flesh side up to the gauge roll. 

Of the various troubles which may happen, or the failures to 
do good work, we can say but little. The same thing seldom 
happens twice, and there may be more than one cure for any 
trouble, but as a rule, if the machine is properly set, the rubber 
roll straight, the rings all the same size and properly adjusted, 
the gauge roll and friction rolls true and straight and the jaw 
in condition to hold the knife, you must split well. Of course, 
the knife is to be kept well ground ; you cannot split with a 
dull knife, and better wear out a knife a few days sooner than 
spoil your work. Be careful not to get oil upon the rubber 
roll, it will soften it and in a short time destroy it. When the 
roll gets out of true or very rough, you must get it ground 
down ; be sure and keep it straight and smooth. The gauge 
roll will require turning off once in a while ; it gets small in the 
middle. The bearings get worn down small and require 
turning up ; when this is done, bore out the brass boxes and 
bush them with brass. After this is once done you have only 
to put in new bushing for a new roll, or for any subsequent 
turning of the old one. Once in a while take the brass rings 



200 THE MANUFACTURE OF LEATHER. 

off the rod and put the end ones in the middle, the middle 
ones on the end. When you do this be sure every ring is sep- 
arate and free to move and at the same time comes up so close 
to the next one that you can just see through them. By thus 
changing them you avoid turning them down so often ; by 
keeping them close together you do not let them tip on the 
rod and make ring-marks upon the split. Use nothing but the 
best oil to oil up the machine, and see that every part is kept 
clean. 

Too much care cannot be taken to prepare the leather before 
splitting. The best way is to wet it thoroughly and pack it down 
until it is entirely moistened through ; it should retain water 
enough so that when you double the leather together and 
squeeze hard you extract a little water. If too dry there will 
be spots in it dryer than others, and such places always split 
differently from the rest. If you cannot wait for it to season, 
the next best plan is to mill the leather in a hide mill; in fact 
it would be a good plan to do this anyway. The plan of tak- 
ing dry leather, wetting it in a tub and splitting at once is bad, 
and you cannot get good work in this way. If you skive the 
leather it should be jacked or stoned down to take the wrinkles 
out of the neck. Do this upon a stoning jack or stoning ma- 
chine, such as have already been described in Chapter XII ; 
you will find that you cannot spend too much time in preparing 
the leather to split, the result being amply better to pay for 
the time. 

As to the amount of work, you must begin slowly and ex- 
amine the work as you go along, but after a time you will find 
you can make about seventy to eighty cuts an hour, or even 
more ; run the machine as fast as it can be fed well. A great 
deal depends upon the feeder; no machine will split well if the 
feeder is not able to do the work without continual stopping to 
pull back or straighten the leather. 

The machines are made in four sizes, viz., fifty-seven inches 
(57 // ), seventy-two inches {72"), eighty-four inches (84"), and 
one hundred and six inches {106"). And can be used to ad- 
vantage on both wet and dry stock. 



SPLITTING LEATHER. 



20I 



The American Tool and Machine Company manufacture 
belt knives of the finest quality for their machines. 

The Vaughn Machine Co., Peabody, Mass., are constantly 
adding new features to their business. Recently they have 
fitted out a shop adjoining their factory for the production of 
belt knives. They have machinery for grinding, polishing and 
straightening, and a special milling machine for cutting the 

Fig. 47. 




bassett's belt knife splitting machine. 



ends before brazing. All these machines are of their own in- 
vention and in use nowhere but in their shop. They claim 
they are making the best belt knives in the country, and the 
appearance of their knives surely assists to sustain this claim. 

The Vaughn Machine Company have also become the sell- 
ing agents of the belt knife splitting machine, made by the 
American Tool and Machine Company, Boston, Mass. 

Fig. 47 shows a recent improvement on grinder rigging for 
belt knife splitting machines. The grinder is so arranged as to 



202 



THE MANUFACTURE OF LEATHER. 



save all floor space, and can be used alike on machines made 
by the American Tool Company, and those made by F. S. 
Bassett & Co., Woburn, Mass., which latter firm make and sell 




the grinder rigging; the price is $50. F. S. Bassett & Co. 
also manufacture belt knife splitting machines, of which they 
have sold a large number to tanners and curriers not only in 



SPLITTING LEATHER. 203 

the United States, but in France, Germany and England, and 
which are all giving complete satisfaction. 

Bassett & Co. claim that their belt knife splitting machine is 
the most convenient to operate of any on the market, and that 
it will leave the leather in condition as good as or better than 
that of any other for the following reasons : 

1 . The machine is strengthened in places which have been 
considered weak in machines built heretofore, thereby making 
it less liable to vibration. 

2. The improvement in regard to the removal of the rubber 
roll shown in Fig. 48 is a great convenience to the operator, 
as in all other machines the work requires about five hours. 
In this machine the roll can be removed in twenty minutes, 
thereby saving half a day's labor, which is quite essential when 
a machine is required to run ten hours per day to keep up with 
the work. 

3. The bevel gears running the machine are absolutely 
noiseless and run perfectly smooth, which is a great improve- 
ment, as the gears used on all other machines not only make a 
great deal of noise, which is very annoying to every person in 
the room, but also tends to corduroy the leather. The ham- 
mering of the cogs when worn a little seems to rattle the knife 
so that in grinding the same it is more apt to leave an uneven 
surface, which tends to corduroy. 

Every machine is guaranteed, and competent men are sent 
with each if required. 

Aside from the above advantages, the Bassett machine has 
all of the modern improvements used on other makes. 

Bassett & Co. also keep on hand emery wheels and all dup- 
licate parts of the belt knife splitting machine. 

Robertson's grinding adjustment for belt knife splitting machines. 

The invention shown in Figs. 49-52 is that of James Robert- 
son, of Woburn, Mass., the most expert splitter on the belt- 
knife splitting machine in the United States. It is in use by a 
large number of the leading tanners in this country and it is a 
valuable addition to the belt-knife splitting machine. 



204 



THE MANUFACTURE OF LEATHER. 



This is an improved movement or adjustment of the belt- 
knife of a leather-splitting machine, whereby opening of doors 
or kneeling by the operator is rendered unnecessary, uniformity 
produced in the bevels on the opposite sides of the knife, and 
economy attained in the wear thereof, all with the effect of im- 



Fig. 49. 




proving the quality of work produced by the splitting-knife. 
The invention consists in the novel construction and arrange- 
ment of parts hereinafter described, and illustrated in the ac- 
companying drawings, in which — 

Fig. 49 is a front elevation of a portion of a belt-knife 
leather-splitting machine with Robertson's improved grinding 
adjustment applied thereto. Fig. 50 is a vertical section taken 



SPLITTING LEATHER. 



205 



on line x, Fig. 49, looking towards the grinders. Fig. 5 1 is a 
horizontal section taken on line j/, Fig. 50. Fig. 52 is a detail 



l Fig. 50 




Fig 51 






in section of a wrench whereby separate hand adjustment of 
one of the grinders may be had. 



2 06 THE MANUFACTURE OF LEATHER. 

A represents a portion of the frame of an ordinary belt- knife 
leather-splitting machine, and A' a bracket attached thereto. 
Secured to the bracket A' is a vertical piece B from which ex- 
tend portions B' which constitute ways for the horizontal 
movement of the slides C, set one above the other, as shown in 
Figs. 49 and 50. 

D D are carriages adjustably secured to slides at D' ', Fig. 5 [, 
and having an independent movement (not new in this inven- 
tion) whereby they may be moved up and down and out of the 
way, if desired, by the hand-wheels d. 

E E' are shafts each having one bearing in a carriage D y 
(the other bearing being as usual, and not new). The shafts 
are driven by the pulleys e e', and have rigidly secured to them 
the grinding-wheels F F '. The grinders F F are set on oppo- 
site sides of the cutting-edge of the endless belt-knife K, which 
is driven in the usual manner, and is guided and supported by 
the grinder-jaw L, which contains a back-plate L' for the pur- 
pose of moving the knife forward as it wears. 

P is a vertical shaft having its bearings in the frame of the 
machine and extending up to a point convenient to the oper- 
ator, so that he can rotate it by means of the hand-wheel P' 
without stooping. On this shaft P are fixed two worms R R' 
which engage, respectively, two gears 5 S' which are fast to 
screws V extending into the recesses b in the ways B' . These 
screws engage nuts W which are secured to the slides C, Figs. 
50 and 51. By rotating the shaft P, therefore, the screws V 
are rotated, thus moving forward simultaneously the slides C, 
and hence the carriages D, which move the grinding-wheels 
F F simultaneously forward against the opposite sides of the 
edge of the belt-knife K, sharpening and beveling both sides 
thereof at once with absolute accuracy, and of course sharpen- 
ing both sides absolutely alike. 

Should it be desired to move forward one carriage and its 
grinding wheel independently of the other, an adjusting wrench 
H, ¥'\g. 52, may be applied to either of the heads h of the 
screws or bolts B, the portion H' of said wrench being used to 
actuate the nut h' on said heads. 



SPLITTING LEATHER. 207 

James Robertson, who is a practical currier of Woburn, 
Mass., also manufactures an appliance for regulating the dis- 
tance of the knife from the centre line of the belt-knife splitting 
machine. This he sells for $3. He also makes another appli- 
ance for regulating the weight of leather to be cut on the belt- 
knife splitting machines, which he also sells at $3. These 
appliances do away with guess-work in operating the belt-knife 
machine and make the work exact. 

He also manufactures a Leather Gauge which will tell in- 
stantly the weight of leather per square foot. 



CHAPTER XIV. 

SCOURING. 

AFTER the leather has been split it is commonly handled in 
liquor for about two weeks, which completes the tanning pro- 
cess, and the next operations to which it is to be subjected are 
the drying and finishing for market. 

Of course different varieties of leather pass through different 
modes of treatment, and while there is but little to be done in 
the finishing of sole leather, except the drying and rolling, there 
is much to be done in finishing upper leathers, Morocco 
leathers, etc. 

We shall therefore devote one chapter to each of the subjects 
of scouring, stuffing, blackening and polishing leather, and then 
for other details of special branches of manufacture and for 
coloring and dyeing leather, refer the reader to the various 
chapters treating of those subjects. 

The tools used in the hand method of scouring leather are 
the brush, stone and slicker; the brush is shown in Fig. 53, 

Fig. 53. 




and the perspective view, Fig. 54, shows the form of tables and 
other mechanical details connected with the hand method of 
scouring leather. 

This manner is laborious and expensive, which has caused it 
to be superseded almost entirely by machinery. 

The Vaughn Machine Co., Peabody, Mass., make brushes 

( 208) 



SCOURING. 



209 



suitable for scouring by hand. These brushes are of excellent 
quality, made from selected bristle. 

monk's scouring machine. 

The Monk scouring machine, shown in Figs. 55 and 56, is 
built by the American Oak Leather Company, Cincinnati, O., 
and it is the simplest, most durable, and cheapest scouring 

Fig. 54. 




machine on the market, and will do more work per hour with 
less power than any other scouring machine which we have ever 
seen. It should be run at a speed of five hundred to six hun- 
dred revolutions per minute. 

It can be used on the following leathers : sole, harness and 
upper, and it is especially adapted for scouring shoe leather 
splits, as it prepares the face of the split leather better and the 



210 



THE MANUFACTURE OF LEATHER. 



split will finish up finer than if scoured on any other machine. 
It is also especially adapted for scouring belt leather, as it 
scours the leather more thoroughly and it will do more work 
than any other machine of its class used in the trade. 

Fig. 55. 




VIEW OF CYLINDER SHOWING STONES IN MONK'S SCOURING MACHINE. 



It has been found by experience that the fine North River 
blue stone in the cylinders does better work than if the cylin- 
ders were filled with stones and brushes. But this is a matter 
for the purchaser of the machine to decide, who can have the 
cylinders filled with stones or brushes as he may desire. 

The leather adjusts itself to the stones during the scouring. 
The stones are not made the full length of the cylinder. Short 



SCOURING. 



211 




212 THE MANUFACTURE OF LEATHER. 

stones cover the openings or gaps left by the preceding stones, 
as is shown in the illustration. 

The same machine can be used as a brushing machine for 
all kinds of leather which may require brushing, by simply fill- 
ing the cylinder with brushes instead of stones. 

Fig. 57 shows the new vertical or upright constructed scour- 
ing and setting-out machine, built by the Vaughn Machine 
Company, Peabody, Mass. The builders claim for this machine 
a great gain in both quantity and quality of work over any- 
thing before known in the currying shop. 

It will scour or set out, in the most superior manner, large 
quantities of upper leather, in grains, buff, glove, bag leather, 
fancy colors, wax, kips, splits or calf skins, and belting leather, 
either in the whole butts or in strips. 

Its construction will at once recommend it for these purposes, 
as being simple, effective, and of the proper principle for doing 
the work, as the side, hide or skin, is placed lengthways on the 
vertical table, one -half on each side of the same, and is carried 
up between the two cylinders, which are revolving toward each 
other, and covered with blades arranged so as to thoroughly 
work and stretch the leather both in width and length at one 
and the same time, as will be seen by the cut of the machine. 
As much or as little pressure of the cylinders is applied to the 
leather as is wanted by the operator, with the foot lever. In 
this way the leather is much more thoroughly stretched, worked 
fine, and made firmer than it is possible to do by hand or any 
other machine. 

In scouring, as will readily be seen from the cut and this 
description, nothing could possibly equal its principle, as the 
revolving cylinders thoroughly work out all the dirt, put the 
leather into perfect shape, and leave it fine, dry, even and 
smooth ; a great point being that all the dirt, water, tan 
liquors, etc., expressed from the leather by the cylinders dur- 
ing this operation, fall to the floor, away from the table, and 
therefore cannot be absorbed by the leather again, as is the 
case in hand work or flat table machines. 



SCOURING. 



213 




214 THE MANUFACTURE OF LEATHER. 

For setting out fancy colored leathers the above points make 
it particularly valuable, and for setting out stuffed leather of all 
kinds, a great point is that it can be worked in a much colder 
and harder state than is possible to do by hand, thereby leav- 
ing the grease and weight in the leather, and having all the 
stretch that is set out, stay out. 

The builders guarantee, therefore, that by the use of this 
machine the currier gets finer leather, and at the same time 
more measurement and weight, besides the saving in labor. 

Made in all sizes from a 5 ft. to a 12 ft. in length of the cylin- 
ders. 

But little power and small space required to operate it. 

It is simple, strong and durable. 



CHAPTER XV. 

STUFFING LEATHER ; OILS AND FATS ; TESTING OILS ; WATER- 
PROOF STUFFING ; WATER-PROOFING LEATHER. 

HAND STUFFING. 

In the manufacture of upper leather, after the sides have 
been scoured as described in the preceding chapter, they are 
exposed to the air to harden and are next carried to the cellar 
of the shop to be dampened and tempered, so as to facilitate 
the absorption of the grease ; the tempering process generally- 
extending through two days. 

The period of tempering depends upon whether the leather 
is to be stuffed by hand or machinery. When stuffed by hand 
the leather requires to be damper than when stuffed by means 
of the wheel. 

Ordinarily the hand process of stuffing leather is accom- 
plished after rolling the sides into bundles with the grain side 
in and softening them by treating or beating, and then apply- 
ing to the flesh side by means of a brush, a mixture of oil and 
tallow in a heated state. In addition to the trouble and ex- 
pense of the hand method of stuffing, another objection arises 
from the fact that the leather has to be dampened to such an 
extent that it necessitates a long period for drying, and then 
again, after the partial absorption of the oleaginous and fatty 
materials, the surface of the leather has to be separately cleaned 
of the unabsorbed matter. 

Another great objection to the hand method of stuffing 
leather is that the stuffing materials, unless great care be ob- 
served, penetrate only slightly beyond the surface, thereby 
leaving the leather, as regards the main body, dry and un- 
changed, and consequently hard. But when the modern stuff- 

(215) 



2l6 THE MANUFACTURE OF LEATHER. 

ing drum is used for this purpose the leather is usually thor- 
oughly permeated and thereby rendered soft and pliable. 

The old method of hand stuffing is now passing away and in 
modern currying shops it is only used for certain classes of 
leathers. 

DRUM STUFFING. 

Drum stuffing is the most profitable, and turns out a more 
salable article. In these days of close competition, i pound 
in weight in a dozen kip butts, or a pair of harness backs or 
strap butts, is a very important item, especially if the same can 
be obtained leaving the goods a better color and a more sal- 
able appearance than if done by hand. It must always be re- 
membered that stale goods will not carry the stuff as well as 
fresh ones, and goods that have had a good sumaching will, 
as a rule, carry the stuff more freely. In preparing the goods 
they should be dried out and then dampened on the flesh and 
grain sides and allowed to lie in a pile for a time covered with 
damp cloths, so that the moisture permeates freely through the 
leather, but not sufficiently so that the water can be squeezed 
out. 

The next point is — what is the best material to use in stuff- 
ing? This depends on the quality of the goods ; if they are 
of the best quality, we recommend the best grade of tallow 
and cod oil, no matter whether harness, strap or shoe work ; 
but if they are of second or inferior quality, and especially if the 
goods are being dressed for the market, we would say that 
there is nothing to beat stearine, mixed with degras and neat's- 
foot oil. 

It is not possible to lay down any fixed rule for stuffings, as 
all depends upon the quality of the tannage, and the grade of 
leather which it is desired to produce. The temperature of the 
drum and the temperature of the stuffing are also points which 
must be influenced by the same considerations. 

In heating the drum close the door and turn on the steam 
for 20 minutes, the drum remaining stationary, then turn off the 



STUFFING LEATHER. 21 J 

steam and disconnect the pipe. It is very important that the: 
steam pipe should be disconnected each time, because after a 
little wear there is sure to be an escape of steam, more or less,. 
and consequently the scalding of goods, which is a very serious 
matter. After disconnecting the pipe, take off the door and 
allow the drum to run for five minutes, so that the steam may 
evaporate, then put in the goods as quickly as possible, and 
put on the skeleton door, and let them run for a few minutes 
before putting in the stuff; by so doing the goods will become 
broken up and more regulated ; then stop the drum, put in the 
stuff, and put on the close door and run the goods for forty 
minutes. The stuff must be put in warm, of course, but not hot 
enough to scald the goods. After running for forty minutes, 
take off the close door and again put on the open door, and 
run the goods for another five minutes ; that will allow the goods 
to cool down and become more even. The putting on of the 
open door is simply to prevent the goods from falling out as 
the drum is revolving. 

The goods may now be taken out and opened out smoothly 
in a pile, and if they are not wanted for setting immediately 
they should be covered and kept as warm as possible, until 
such time as they are wanted for setting. What is best after 
taking from the drum is to place the goods in an air-tight box r 
until such time as they are needed. By keeping the goods 
moist and keeping them warm much labor will be saved in 
setting, and they will look much better for it. It is best to 
set the goods as early as possible after removal from the drum,. 
for if they are allowed to become cool, it is almost impossible to 
get out the stretch. When the goods are unavoidably allowed to 
lie and get cold, it is well to have a tub of water by the side of 
the stuffing table, and dip in each side to soften it before pro- 
ceeding to set the same. In setting, we recommend the use of 
marble or plate-glass tables, as they do not leave any impres- 
sion on the flesh side after stoning, but give a smooth and close 
appearance to the flesh side, thereby saving both leather and 
labor in whitening. The goods should be stoned on the grain 



2l8 THE MANUFACTURE OF LEATHER. 

with fine stone, until all old or growth grain is removed, then 
hung up nearly dry ; then again take down and glass on the 
grain, removing all stone marks, and giving pattern to the 
leather ; then again hung up until dry. 

REED AND WINCHESTER'S STUFFING DRUM. 

The stuffing drum shown in Figs. 58 and 59 is the invention 
of Reed and Winchester. 

This invention in stuffing leather has for its object a method 
whereby the grease may be put into the leather more regularly 
than heretofore. The leather must be warm, and be kept warm 
uniformly during the time the grease is being applied to it. 

The leather to receive grease or stuffing is usually placed in 
a rotating drum or wheel previously heated by steam or hot air 
blown into it while the wheel is empty, for it has been found 
that steam injected into the drum in the presence of the leather 
is apt to burn it. A drum heated only before placing the leather 
in it commences to cool immediately thereafter, and the stuffing 
or greasing operation is retarded. Another serious objection to 
the direct introduction of steam into the drum with the leather 
and grease is that arising from water of condensation, as even 
a small amount of water added at that time, the leather having 
been evenly and sufficiently moistened before it was placed in 
the drum, will be taken up by the leather, thus lessening the 
amount of grease entering the leather at that spot where the 
water of condensation in the grease meets the leather, and, 
further, the heat derived from free steam varies materially, 
according to the pressure of steam in the boiler. To obviate 
the objection of free steam the drum has been placed in a sec- 
ond drum heated by steam. 

In this invention the interior of the drum and leather therein 
are kept at the desired temperature by means of heated air 
forced therein while the drum containing its charge of leather 
is being rotated. The hot air is supplied to the drum by a 
blower or pump through pipes, in connection with a receiving- 
chamber of a suitable heat-generating apparatus. 



STUFFING LEATHER. 



219 



Figure 58 represents, in vertical section, an apparatus em- 
bodying Reed and Winchester's invention, the wall of the heat- 
generating apparatus being also in section. Fig. 59 is an 
elevation of the left-hand end of the drum, the latter being 
partially broken out. 

The drum, a, about seven feet in diameter, has a door, b, for 
the introduction of the leather therein, and a series of pegs, c, 
at suitable intervals apart to lift and tumble the leather as the 
drum is rotated, all as usual. This drum has at one journal a 
pipe, d, for the introduction at suitable times of hot grease, and 
at its other journal it has a pipe, e, for the continuous admission 
of hot air while the drum is being rotated with the leather and 
grease therein. The pipe e is preferably placed, in coil or other 
form, in the combustion-chamber f, heated in any usual way, 
so that air forced through the pipe by an air-forcing apparatus, 

Fie. 58. 




g (shown as a blower, but which might be a pump), will be 
heated before reaching the drum. The side of the drum will 
be provided with openings of suitable size for the escape of the 
heated air, so as to maintain proper circulation. The air so 
escaping might be delivered into an annular chamber, h, placed 
next to the openings of the wheel (see Fig. 58), having a pipe, 
i, to lead the air out of the building, if desired. 



220 



THE MANUFACTURE OF LEATHER. 



The air-pipe, at a point between the chamber f and drum, 
may have a branch, k, by which, if desired, to divert the heated 
air into a water-box and over a pan of water, to thus add a 
little moisture to the hot air, if too dry ; or we may inject a 
small amount of steam into the pipe e containing the hot air, to 
slightly moisten it, care being taken to so regulate the steam 
that no water of condensation is permitted to form or enter the 
drum. 

In this process it is possible to keep the interior of the drum 
and the leather therein at a uniform temperature, which may be 

Fig. 59. 




indicated by a thermometer properly connected with the drum, 
which enables the leather to be greased or stuffed uniformly 
and rapidly, and that without fear of injuring the leather in any 
wa3>- by over-heating, as when steam is depended upon, or by 
too rapid cooling, as when the drum is heated only before ap- 
plying the leather. The grease, in proper quantities, can be 
introduced from time to time, as needed. 

This valuable invention appears to have been suggested by 
that of Dr. Friederich Knapp, of Brunswick, Germany, who in- 
vented an improvement in tramping-drums in 1878, which pos- 
sessed the combination of the drum and hollow trunnions and 



STUFFING LEATHER. 



221 



the blower or fan and other arrangements very similar to the 
stuffing wheel which has just been described ; but while our 
Government granted Knapp a patent for the fan attachment 
to the stuffing wheel, the German Government had previously 
refused it as not being a new idea. 

freeman's stuffing drum. 
J. T. Freeman & Co., Woburn, Mass., manufacture all kinds 
of stuffing and tanning drums, driven either with a gear on the 
outside or on the end, as shown in Fig. 60, as parties may 
desire. 

Fig. 60. 




The machines made by this firm are all put together in the 
best possible manner, and are in every way fitted for the work 
required of them, and they offer them to the trade, feeling that 
they will prove completely satisfactory, and they guarantee 
them to be in all respects as represented. Their machines are 
in use in the establishments of nearly all leading tanners and 
curriers in the United States. 

curriers' oils and grease. 
Oil is the general name for a class of bodies which have all 



222 THE MANUFACTURE OF LEATHER. 

or most of the following properties in common: They are 
neutral bodies, having a more or less unctious feel and viscous 
consistency, are liquid at ordinary temperatures, are lighter 
than water, and are insoluble in it, but dissolve in alcohol and 
more readily in ether, and take fire when heated in air, burning 
with a luminous, smoky flame. 

The name oil is made to embrace three distinct classes of 
bodies: I, fixed or fatty oils; 2, volatile and essential oils, and 
3, petroleum and other mineral oils. The first class comprises 
a number of organic bodies, composed of carbon, hydrogen 
and a little oxygen, viscid liquids, communicating a permanent 
stain to paper, insoluble in water, and as they occur in nature, 
mostly mixtures of different simple fats, which, by saponifica- 
tion, are resolved into fatty acids and glycerine. The term fat 
is applied to these oils when they are in a solid state; thus the 
same product may be an oil in one climate and a fat in another. 
The second class, volatile and essential oils, consist either 
wholly of carbon and hydrogen, or of these elements supple- 
mented by less proportions of oxygen, nitrogen and sulphur. 
They have a thin, oily consistence, volatilize completely at a 
high temperature, possess powerful and peculiar odor and flavor, 
and are very inflammable and sparingly soluble in water. Many 
of them occur ready formed in organic bodies, chiefly of the 
vegetable kingdom, and are then true essential oils ; others, 
which are volatile but not essential, are produced by dry dis- 
tillation, fermentation and other changes. The third class, 
mineral oils, belong strictly to the preceding, being truly vola- 
tile oils. 

In a fresh state the fats are odorless, tasteless, colorless or 
white bodies, which may be either solid or liquid. They are 
insoluble in water and cold alcohol, but dissolve freely in ether, 
chloroform and benzine. The solid neutral fats, like sperma- 
ceti, suet and lard, and the liquid non-volatile oils, like sperm 
and olive oil, are classed together as fats. They are compound 
ethers formed by the union of fatty acids with the triatomic 
alcohol glycerine. They are composed of carbon, hydrogen 
and oxygen, but contain no nitrogen. 



STUFFING LEATHER. 223 

The most common and abundant are stearin, palmitin and 
olein. Of these, stearin and palmitin are solids at ordinary 
temperatures, and olein is a liquid. Most animal and vegetable 
fats are mixtures of two or more of the simple fats, and their 
hardness depends largely on the relative quantity of olein or 
other liquid fat in them. When a fat is treated with an alkali, 
the fatty acid unites with the alkaline base, making a soap, and 
glycerine is set free. When a soap is treated with an acid, the 
base is taken from the fatty acid, which is thus set free. 

Neither essential nor mineral oils can be spoken of as fatty 
substances. So far as these are of interest to tanners and cur- 
riers they will be here described. 

For leather there is probably no oil that combines so many 
points of excellence as strictly pure cod oil, which is obtained 
from cod liver, and is produced in quite large quantities, and 
has stood the test of experience and trial for a very long period 
of years, dating back to the earlier stages of the leather industry. 

The reasons for the excellence of cod oil for leather purposes 
are not hard to find. 

In the first place, it has a splendid body, and imparts to the 
leather a permanent mellow feeling, by reason of its freedom 
from oxidizing (caused by absorption of oxygen from the air) 
common to a great many other oils. 

Cod oil absorbs oxygen, or in other parlance, gums, to the 
smallest appreciable extent only, and for that reason, together 
with its great body and freedom from evaporation, remains in 
the leather under the same conditions practically, in which it 
was originally put in. 

The best quality of cod oil comes from the Newfoundland 
Fisheries, where the method of extracting the oil from the liver 
in a cool atmosphere, extracts only the cream of the oil, which 
is very rich and contains the minimum of animal fibre, blood, 
gluten, etc., thereby insuring the very best results. 

This oil commands the highest price in the market, and is 
worth the difference in cost between it and cheaper grades, or 
any adulterations. 



2 24 THE MANUFACTURE OF LEATHER. 

Some of the adulterants used by unscrupulous dealers are 
mineral oils of various kinds, including paraffine oil, as well as 
brown seal and menhaden oils. 

Cod-liver oil is a valuable oil afforded by the liver of several 
"fish of the genus Gadus, notably that of the common cod. The 
chief seats of the cod-fishery are the coasts and banks of New 
Foundland, Nova Scotia, the Gulf of St. Lawrence, the west 
coast of Norway, from Stavenger nearly up to Hammerfest, and 
including the Lofifoden Islands ; the coasts of Denmark and 
Germany, commencing at Romo on the west, passing through 
the Skager Rack and Cattegat, and extending east to Dant- 
zig; the coasts of Shetland, Faroe and Iceland, the Dogger 
Bank in the North Sea, and the most prolific of all, the shores 
of Alaska in the Pacific Ocean. The most usual classification 
ior cod-liver oil is into 1st, steam-boiled medicinal or ordinary 
bright; 2d, an inferior "light brown," and 3d, the "dark 
brown" or "tanners'," obtained by roughly boiling down the 
livers remaining after the other two oils have been extracted. 
The best is said to be from New Foundland. The chemical 
and physical characteristics of the 3d grade, the only one in 
which we are interested, are as follows : The color is dark 
brown, greenish by transmitted light; specific gravity 0.929, 
at 63 j4° F. ; soluble in 1 7-20 parts cold or hot absolute alcohol ; 
•deposits no solid fat at 90 F. The oil consists chiefly of 
oleine and margarine, and contains small portions of iodine, 
bromine, and free phosphorus, besides peculiar constituents. 
Many other oils are substituted for true cod-liver oil. That 
obtained from the ling, the liver of the dorse, and of the coal- 
fish, the barbot, the haddock, hake, cat-fish, conger eel, ray, 
shark, and probably many others, are surreptitiously mingled 
with the cod-liver oil of commerce. 

Genuine cod oil is made wholly from the liver of the fish, 
while menhaden oil is squeezed from the body of the fish. 
The latter oil has more gum or glutinous matter than the gen- 
uine cod oil. Mineral oil improves it by cutting the gum, and 
this is the reason that cheap cod oils are often used without 



STUFFING LEATHER. 225 

trouble. Cod oil and menhaden oil are of the same color and 
gravity, and resemble each other as to odor and taste. These 
similar properties make deception very easy. A better and 
more economical way than to buy cheap "cod oil" is to buy 
pure pressed menhaden oil and buy paraffine oil and combine 
the two oils in the proportions wanted. The pure cod oil is, 
however, everything considered, cheapest in the end. As long 
as dealers are determined to get large profits and tanners are 
deceived, the selling of cheap fish oils for cod oil will continue. 

Mineral oils are easily detected by several well-known tests, 
such as the gravity test, as the admixture of mineral oils re- 
duces its body or substance, and when compared with strictly 
pure oil, the difference can at once be seen. Another method 
of detecting mineral oil is by saponifying the fatty oil, whereby 
the mineral oil, which will not saponify, will separate. Another 
method is to distil off the mineral oil by heat of about 440 
Fahrenheit, thus leaving the non-volatile oil behind. 

Adulterations of brown seal and menhaden oils are almost im- 
possible to detect chemically, but the bad effects will appear 
only after the leather has been finished, when it is too late to 
remedy them. 

The only safeguard for the tanner is to obtain goods from 
strictly reliable houses only, of known reputation, and to take 
only such brands as are known to be strictly and absolutely 
pure and as represented. 

Considerable quantities of cod oil are produced in the Pro- 
vinces, and also from the various Fisheries in the United States, 
the general principle being that the deep-sea oil, made in a 
cool temperature, and thoroughly rendered, produces the best 
results. 

Bank and Straits oils are used as substitutes for cod oil and 
for some purposes seem to answer very well. Both of these 
kinds are subject to absorption of oxygen, or in other words, 
gumming, when exposed to the air, Straits oil being a little 
lighter in color, and generally bringing one or two cents more 
per gallon. 

!5 



226 THE MANUFACTURE OF LEATHER. 

Degras, the imitation variety, is a wool grease, reclaimed from 
washing of wool, and varies in excellence owing to the kind of 
wool washed, the method of saponification or scouring soap 
used in the process, and thirdly, upon the method of recover- 
ing the grease. 

Where either of these methods is poor, the resultant grease 
is bad. There is therefore quite a range in price to correspond 
with the different qualities. 

Some degras is not fit for use on leather, as it is imperfectly 
made or not properly purified. 

Large quantities are imported into the United States from 
England, France and Germany, but great care should be exer- 
cised to secure the proper goods in order to obtain the best 
results. The true degras comes from France. 

It is safer to use only the best and well-known brands, which 
are carefully and uniformly made, and are by test and experi- 
ence known to be of uniform quality and excellence. Among 
such reliable goods, which have been on the market and most 
favorably known for a great many years, are the "Anchor" 
and the " Merino." 

English sod oil is a product resulting in the oil tannage of 
skins, which are allowed to heat slightly by exposure to the at- 
mosphere in moderately warm temperature, and the excess of 
oil is thereafter pressed out, or washed out with a weak alkali, 
as the case may be, some employing both methods and some 
only one in extraction ; but as a rule, both are used, and the 
resultant oil makes the sod oil of commerce. 

It will be at once apparent that there is an opportunity for a 
great variation in quality of sod oil, dependent upon the 
methods employed, the kind of skins treated, and the kind of 
oil originally used for tanning. Therefore, the currier must be 
careful to buy only those kinds that he knows are adapted to 
his particular finish if he would get the best results. 

Some of the sod oil is boiled after having been expressed 
from the skins, and the water evaporated out. Other brands 
have more or less water in combination. 



STUFFING LEATHER. 227 

It will therefore be seen at once that here is a chance for 
wide variation in price, to correspond with the difference in 
quality. Therefore the experienced purchaser or handler can 
by selection suit the individual currier with such goods as he 
may require. 

French moellon oil, strictly speaking, is an expressed oil 
from chamois tannage, French degras being a mixture of 
moellon and oil obtained from washing the skins in an alkaline 
solution. 

"Imperial" French moellon is as good an article as there is 
on the market, and is always reliable and safe. 

Tallow is not so generally used as formerly in the manufac- 
ture of upper leather, because other harder and dryer greases 
are obtainable, of strictly uniform quality, that seem to serve 
the purpose better. If tallow is used at all, only the harder and 
purer kinds, that contain no bone grease or other adulterations, 
should be used in order to get the best results. 

Strictly pure rendered tallow, made from fresh fat, is by far 
preferable, as it is harder and contains less moisture than the 
ordinary cheap tallow rendered by steam. 

Oleo-stearine, a product of the best suet tallow from which 
the oil has been expressed, is considerably used for stuffing of 
leather, and is a desirable article, although if used alone it does 
not give a satisfactory finish, being too dry and husky. 

Paraffine wax should not be used in large quantities, because 
it has very little real body, its hardness being apparent rather 
than substantial. When melted, it is a very thin liquid, of ex- 
tremely high gravity, and its apparent substance is due to the 
fact that it chills at about 125 F. 

The principal stuffing used for upper leather is a brown, hard 
grease, made principally from rendered whitening and table 
grease, and this compound seems to give better results and 
produce leather of more uniform excellence than any other 
grease now before the public. 

The reason for this is not hard to find, for the material is 
virtually a stearine, from which the oil has been absorbed in- 



228 THE MANUFACTURE OF LEATHER. 

stead of pressed, thus making a desirable compound of the 
right body to thoroughly fill the leather, and at the same time 
make it mellow and good. 

Competition has brought the price down to the lowest figure 
ever known, and the best brands are obtainable at prices nearly 
as low as ordinary tallow. 

The "Ideal" grease probably combines as many points of 
excellence as anything in the market, and its use is rapidly ex- 
tending, especially for split, grain and satin leather. In the 
manufacture of this grease comparatively new methods are 
employed, and the result is a scientific compound which pro- 
duces the best stock at a minimum price. This grease is pre- 
pared by Frank L. Young and Kimball, Boston, Mass. 

Neatsfoot oil is used largely in the manufacture of kid and 
skins of various kinds, and works very well if care is taken to 
secure oil that has been refined sufficiently to stand a first-rate 
cold test. Otherwise the skin is liable to turn white after 
being finished and exposed to a cold temperature. 

A great deal of damage may be done by using impure or 
imperfectly manufactured oil, and great care should be exer- 
cised in getting the right kind of goods. 

The Vici brand of neatsfoot oil is a well-known brand which 
has stood the test of years and experience. 

MENHADEN, STRAITS OR BANK OIL 

A fish once eagerly sought for its oil on the Atlantic coast is 
the menhaden, pogy, mossbunker, bony fish, chebog, as it is var- 
iously called, (alosa brevoordia menhaden), a member of the 
herring family, about eight to fourteen inches long. The fish- 
ery is carried on all along the coast from Maine to Maryland. 
The fish leave the Gulf Stream and strike the coast of New 
Jersey in April, reaching the coast of Maine in May or June, 
and remaining till October or November. They migrate in 
enormous schools and are caught in seines. These fish are 
nearly all boiled down to oil in steam kettles and exposed to 
hydraulic pressure ; the scrap being utilized for fertilizers. The 



STUFFING LEATHER. 229 

oil is clarified and bleached by boiling and filtering. Thus 
refined it is called " straits." Bank oil is an inferior grade. 
Bleaching the oil is done by exposing it to the sun in glass- 
covered shallow tanks. Owing to the tendency of menhaden 
oil to gum, it is not much used now in the leather industry. 

PORPOISE OIL. 

Porpoise oil embraces the oils obtained from the black por- 
poise, the white whale, the grampus and the blackfish. A full 
grown porpoise attains a weight of 2,500 to 4,000 pounds, and 
gives some 400 to 450 pounds of oil, which is more esteemed 
than that of either the seal or walrus. These animals are taken 
by being surrounded by enclosures made of light flexible poles 
driven into the beach, within which they are speared and 
harpooned from boats. The oil is inodorous and gives a bril- 
liant light, it congeals only in intense cold, and its softness 
renders it valuable for lubricating and leather dressing. 

The oil obtained from the head of the grampus is thought to 
be even superior to any yet obtained from the porpoise and the 
black-fish, but this cetacean occurs much more rarely than 
either of the animals just described. 

TUNNY OIL. 

The tunny is second in importance only to the sardine 
among the fish caught in the Mediterranean. This fish yields 
a very large quantity of oil which is extracted by boiling, which 
operation is performed in the crudest possible manner. Tunny 
oil is of a pale amber color, and possesses more body than 
any other fish oil. It is very commonly adulterated with in- 
ferior cod oil and cotton-seed oil. That prepared at Genoa is 
said to be superior to all others. 

NEATS' FOOT OIL. 

Neats' foot oil is made from " ox feet," the feet and hocks of 
neat cattle cut off about eighteen inches above the hoof, and 
is a valuable oil. It is prepared by denuding the feet of skin 



230 THE MANUFACTURE OF LEATHER. 

and slitting up longitudinally, by a knife passed between the 
sections of the hoof and continued between the long bones. 
Near the hoof is a small mass of soft fat, which is scooped out 
with a knife, and set aside for the preparation of the best 
quality of oil. The hoofs are washed in cold water and then 
boiled. A certain quantity of oil is thus boiled out of them, 
and when skimmed off, forms an inferior grade of neats' foot 
oil. After about three hours' boiling, the tissues between the 
horny hoofs and the last digit bone are sufficiently softened to 
allow of the latter being easily scooped out of the hoof with a 
knife. These " cores," consisting of bone, gelatinous matter 
and fat, together with the small pieces previously alluded to as 
being removed by the knife before boiling, are put into a 
separate pan of fresh water, and all boiled together for the ex- 
traction of the oil. This forms the best kind of neats' foot oil. 
The oil is usually yellowish or greenish in color, but that from 
Buenos Ayres is often colorless. It is odorless when fresh and 
of agreeable flavor. It is limpid and remains so below a 
temperature of 32 F. Its density at 59 F. is 0.916. On 
standing for a short time, a proportion of solid fat separates 
out, and may be filtered off. It is very rarely found pure. 

DEGRAS. 

We have only to speak now of degras, the surplus oil from 
the chamois leather manufacture, which, in France is prepared 
by daily stocking the skins with oil, and hanging in the air 
for oxidation. The degras is obtained not by washing the 
skins in an alkaline lye, as in the English and German method, 
but by simply pressing or wringing. This oil, altered by oxi- 
dation, is so valuable for currying purposes that skins are 
frequently worked simply for its production, being oiled and 
squeezed again and again till not a rag is left. It is generally 
mixed in commerce with more or less of ordinary fish oil. 
Eitner recommends, where the degras is of indifferent quality, 
a mixture of 65 parts degras, 20 of neutral soap (i. e. soap 
without the usual excess of alkali), and 15 of soft tallow. 



STUFFING LEATHER. 23 I 

A degras is used in England called Vickers' degras. It is 
more softening than sod oil, and carries the tallow well into the 
leather. Hides left in it for some time are not darkened. If 
stearine is used, 20 to 35 per cent, of degras obviates harsh- 
ness, and goods will be firm yet mellow. In cheap lining 
bellies, this degras, used instead of cod oil, gives better weight, 
lighter color, and a good " calf " handle. It is much cheaper 
than French degras. 

The use of sod oil or French degras, for stuffing bark-tanned 
leather, dates as far back as the last century. At that time 
curriers used it mainly in the form of " fat liquor," although a 
considerable quantity was also used as " sod oil." At that 
time sod oil was made from fat liquor by decomposing the 
same with alum ; otherwise the process was the same as to-day, 
where sulphuric acid is used to "throw out" the sod oil. The 
use of sulphuric acid offers no advantage over alum except 
being a little cheaper, while on the other hand, sulphuric acid 
is a very dangerous enemy to leather. If the acid used for 
making sod oil is added even in small excess, it will be carried 
with the sod oil into the leather and there surely work havoc. 
Leather stuffed with such sod oil is very liable to get tender, 
and logwood black will be apt to fade if sulphuric acid comes 
in contact with it. We have tested numerous sod oils which 
contained quite a considerable quantity of sulphuric acid. It 
is often thought that heating a sod oil will drive off any sul- 
phuric acid. This notion is erroneous, as sulphuric acid is not 
volatile below 590 F., and sod oil at this temperature would 
be burned to charcoal. The only practical way of getting rid 
of an excess of acid in sod oil is to boil it with a weak solution 
of soda or other alkali. The alkali will combine with the acid 
and leave the latter powerless to do any damage. When 
French calfskins had become renowned for their superiority, it 
was found out that the principal factor of their stuffing con- 
sisted in French degras (sod oil). Curriers in other countries 
began to imitate the French, and soon found that they got a 
superior article of leather by using French degras in combinaT 



232 THE MANUFACTURE OF LEATHER. 

tion with other greases. The method used in France for 
tanning oil-dressed leather, and for making sod oil, differs 
radically from that in use in other countries. The French pro- 
ceed about as follows : After the usual beam-house operations, 
the skins intended for chamois leather are oiled on the table 
with fish or whale oil and folded in cushions. The cushions 
are now subjected to the action of the fulling mill for an hour 
or two, then hung out in the open air to cool off, from one-half 
to one hour, and after piling in a heap for a few hours they are 
again fulled. These operations are repeated for several weeks, 
giving the skins an occasional oiling off between the hillings. 
After being completely tawed the skins are generally soaked in 
fish oil for a short time and then put in presses to squeeze out 
the surplus oil that has not chemically combined with the 
fibre. This surplus oil constitutes genuine French degras. 
If the production of French degras be the main object, poor 
skins are taken and the above process of fulling, etc., and 
pressing out the oil or degras, is repeated. Thereby a second, 
third, etc., quality of degras is produced. In fact there are a 
number of establishments in France and Austria that do not 
produce any oil-dressed leather, but which manufacture only 
French degras. These factories use only poor skins and offal 
and keep on tawing the same and pressing out the degras, 
until only a few shreds and fibres are left of the skins. Genu- 
ine French degras has the appearance of thick oil and is 
perfectly liquid, so that it can be poured from one bottle to 
another with ease. It contains no product of saponifica- 
tion or alkali of any kind. In speaking of the different pro- 
cesses of oil-dressing we shall call that used in most European 
countries, except France, simply the European. The process 
generally used in this country and that used in Europe, differs 
radically from that in use by the French. In the American, 
as well as the European, process of oil- dressing the skins go 
through a heating process, which heating changes the sod oil 
in the skins from a thin fluid oil to a thick, viscous mass. In 
this country the skins, after leaving the beam-house, are oiled 



STUFFING LEATHER. 233 

off and then milled for about an hour and hung up for a short 
time to cool, and then milled again, etc., as in the French pro- 
cess. After being completely tawed they are hung in a hot 
room until they are thoroughly heated and completely dry, 
and are put through a last milling and heating process called 
"milling off." During this "milling off" the skins become 
very hot, and care must be taken that they do not scorch. 

The European method of oil-dressing is again different from 
the American and French processes. In the European process 
of chamoising the skins, after leaving the beam-house, they are 
oiled off, and three to four skins made into a cushion, and 
these cushions are milled for three to four hours. After oiling 
off they are again milled, and after getting a third oiling they 
receive another milling ; after which they are hung in the air a 
short time to evaporate a part of the moisture in the skins, and 
the process of oiling and milling is then continued. Sheep-skins 
require six to eight oilings and millings to be completely tawed ; 
hides ten to twelve. After being sufficiently tawed, the skins are 
put through a heating much more intense than is customary in 
this country. The heating or fermentation causes the oil to oxi- 
dize and thicken. Consequently, the longer and more intense 
the heating is conducted the thicker and more viscous will be 
the resulting sod oil. Thus we find the genuine French sod oil 
fluid. The American is so thick that it cannot be poured from 
one vessel into another, and the European sod oil is a mass 
almost as thick as dough. In their specific action on leather 
there seems to be very little difference. We would remark that 
the description of the properties of the different sod oils per- 
tains only to natural sod oils made according to the processes 
as described, and not adulterated with foreign oils. Owing to 
this difference in their physical properties, the American and 
European sod oils are recovered from the oil-dressed leather by 
washing with an alkali solution and decomposition of the fat 
liquor with sulphuric acid ; while the French sod oil is recov- 
ered by simply pressing or wringing out the surplus oil. It 
would be found a very tedious job to make sod oil in this coun- 



234 THE MANUFACTURE OF LEATHER. 

try by simply pressing the oil out of the leather, owing to its 
heavy body. It was, until recently, believed that the fish oil 
used in oil dressing was changed to sod oil by oxidation. This 
theory seemed very plausible for several reasons. Heat is 
always liberated by milling with oil, and the only properties of 
genuine sod oil that were generally known, viz. : the specific 
odor and the property of not gumming with water, could be 
given to fish oil by artificial oxidation. But the most valuable 
and characteristic property of genuine sod oil has never yet 
been produced artificially, and this property is the tanning 
principle of pure sod oil. Pure sod oil contains from 15 to 20 
per cent, of a substance that will chemically unite with the fibre 
of partially tanned leather, or with raw hide which is stuffed 
with it. This substance, when separated from sod oil, is a 
dark brown, brittle body, resembling in its appearance dry 
hemlock extract. The tanning principle of pure sod oil is the 
cause of the high esteem in which it is held as a leather stuff- 
ing ; and there is no doubt that it is this substance that gives 
to sod oil different properties from the ordinary oils and 
greases, making it so valuable to the currier. Therefore, arti- 
ficial sod oil, if of good quality, while possessing some valuable 
properties lacks the most important one of natural sod oil. 
The tanning principle present in natural sod oil effects a re- 
tanning process in leather stuffed with it, at the same time 
imparting to it that velvety feel peculiar to leather stuffed with 
natural sod oil. If, therefore, leather which is not sufficiently 
tanned, be stuffed with grease containing a percentage of real 
sod oil, it will undergo a retanning, and a nice mellow product 
will be obtained, which, otherwise, would not have been the 
case. Besides real sod oil, the only oils or grease known which 
contain a small percentage of this tanning principle, are the 
fish oils. 

Menhaden Bank and Straits oils contain usually about one 
to five per cent, of tanning principle. One sample of genuine 
cod oil, which, by the way, is a very scarce article, contained 
seven per cent, of tanning principle, while other samples of so- 



STUFFING LEATHER. 235 

called cod oil, analyzed by us, did not show much more than 
Menhaden Bank or Straits oil. The value of fish or cod oil as 
a leather lubricant is largely dependent on the amount of tan- 
ning principle contained therein, and an oil containing eight 
per cent, of this substance is really cheaper at thirty-two cents 
than another oil with one per cent, tanning principle would be 
at twenty-three cents. Again, very many cheap fish oils may 
be better suited for oiling and chamoising leather than a high 
priced cod oil. We have tested a number of samples of cod oil 
that did not contain more than one and a half per cent, of tan- 
ning principle. Another point of interest is the fact that fish 
oils, rich in tanning principle, are much less liable to "gum" 
than those which contain a smaller percentage of this substance. 
More than one-half the sod oils sold in this country are either 
wholly artificial or they contain but a small percentage of 
natural sod oil, and do not contain more than two to five per 
cent, of tanning principle. We therefore claim that about the 
same results could be obtained if a good fish oil was substituted 
for such artificial sod oil for stuffing leather. 

PARAFFIN WAX. 

Paraffin wax is a mineral product destined to largely displace 
tallow and oleo-stearine in the manufacture of wax upper kids, 
calf skins, oil grains and harness leather. 

It is but a few years since paraffin wax, a by-product of 
paraffin oil, was introduced as a substitute for tallow, oleo- 
stearine and other heavy greases, in the manufacture of leather. 
Like all innovations, it met with decided opposition from tan- 
ners educated to the belief that animal greases are the only 
suitable ingredients for "stuffing," or filling the pores and cells 
of leather, thereby rendering the fabric practically waterproof, 
as well as producing that supple and greasy finish so desirable 
for the boot, shoe and harness manufacture. 

Paraffin wax has all the filling properties of oleo-stearine, 
together with other good qualities of its own. It will not 
evaporate by long use ; it will not dry or gum by exposure to 



236 THE MANUFACTURE OF LEATHER. 

the inclemency of the weather, and it can be melted at a 
temperature of 124 to 126 degrees F., in connection with tallow 
or degras. At this temperature the greases are readily ab- 
sorbed, if the stuffing wheel is employed. Indeed, the stuffing 
wheel is the only practical method of forcing heavy greases 
into the pores and cells of leather. As the tanners become 
more conversant with the filling and preserving properties of 
paraffin wax, they will be averse to paying for oleo-stearine, 
when the wax will give equal satisfaction, and at a lower cost. 

Tanners, as a rule, are slow to adopt or even experiment 
with new materials, but within the past year, and largely due to 
the almost prohibitive prices of oleo-stearine, paraffin wax has 
been successfully introduced. We learn that it is securing a 
strong foothold in many tanneries. Where it has been ac- 
corded a fair trial, satisfactory results have followed, and there 
have at times been duplicate orders for car lots. 

A tanner who keeps pace with the times must be constantly 
on the alert to secure tanning and finishing materials on a basis 
that will allow him to successfully compete with his neighbor, 
and without in the least deteriorating the quality of his pro- 
duce. It has become necessary to look for economical sub- 
stitutes for bark, oils, tallow, and, indeed, for all that enters into 
the leather manufacture. Oleo-stearine when first introduced 
to tanners was regarded with suspicion, because of the belief 
that all the best properties were extracted in the manufacture 
of butterine. The tanners have since learned that they cannot 
do without it, especially in warm weather, and the same may 
be said of the compounders of lard. 

GLYCERINE. 

The introduction of mineral salts in the manufacture of 
leather created many changes in the trade, and almost revolu- 
tionized the methods then in use for currying and finishing; 
many ingredients hitherto unknown were brought forward, 
amongst which was glycerine. 

This article now takes a very prominent part, and that part 



STUFFING LEATHER. 237 

is after tannage to relieve the tension of the fibre of the stock, 
so as to take what other ingredients may be required to make 
it perfect leather, and at the same time to impart a feel to the 
leather that cannot be produced with any other fatty matter. 
It may be of interest to know how this article is produced. It 
is a liquid obtained by the decomposition of fats and fixed oils, 
and containing not less than 95 per cent, of absolute glycerine, 
a sweet principle, obtained from fats and fixed oils and con- 
taining a small percentage of water. It is a clear, colorless 
liquid of syrupy consistence, oily to the touch, hygroscopic, 
without odor, very sweet and slightly warm to the taste, and 
neutral in reaction. It is soluble in all proportions in water 
and in alcohol, also in a mixture of 3 parts of alcohol and 1 
part of ether, but insoluble in ether alone or chloroform, benzol, 
or fixed oils. In proportions glycerine is intermediate between 
water and the oil ; when exposed to the air it gradually absorbs 
moisture. Glycerine possesses great powers as a solvent, es- 
pecially those of the chlorides of potassium and sodium of the 
alkaline earths. It also dissolves the vegetable acids, and par- 
ticularly tannic acid. It is known that certain neutral vegetable 
substances are far more soluble in glycerine than in water. 
Glycerine does not evaporate when exposed to the air, nor can 
it be distilled without decomposition unless in the presence of 
water or steam. Pure glycerine is very essential where it is to 
be used on leather, and these precautions should be taken. 

See that its consistency is up to standard, and that it is 
neutral (this can be ascertained by litmus paper). C. P.White 
30 is generally used, and is by far the safest to buy. 

From the time that the special property of glycerine of 
softening leather and rendering it supple became known, it has 
largely been used for oiling in the place of fat or degras. 
Although glycerine is capable of imparting to leather a high 
degree of softness and suppleness, it is incorrect to credit it 
with actual preserving properties. It is equally wrong to re- 
gard the suppleness it imparts to leather as a direct nourish- 
ment and strengthening. In this respect glycerine does not 



238 THE MANUFACTURE OF LEATHER. 

replace the fats, which may be considered as direct nourishers 
of the leather, while the former, in spite of suppleness it im- 
parts, also possesses a certain corroding, lixiviating alkaline 
effect. For this reason, glycerine, though advantageous its 
direct effect may be, should never be used alone for oiling and 
softening leather, the more so as wet and humidity will readily 
wash it out, whereby its influence is rendered nil; besides this, 
when the glycerine is expelled it also carries away certain soft- 
ening constituents of the leather itself, which had partly be- 
come dissolved in the glycerine, thereby leaving a leather that 
has become to that extent harder. This is the more worthy 
of attention, as it is quite frequent that glycerine rubbed into 
leather is expelled from it by the influence of wet ; and although 
the use of this unguent has become a custom everywhere, the 
currier should avoid using it alone for oiling leather, but mix it 
previously with supplementary ingredients — in other words, 
prepare it first in a corresponding manner. 

Glycerine of itself is wanting in the proper power of binding 
it to the leather, which is due to its exceedingly great solu- 
bility in water. Attempts were formerly made in practice to 
correct this want by previously rubbing the leather slightly 
with glycerine, and then, as it were, giving it a more' substantial 
covering of melted tallow, but in this procedure the effect of 
the glycerine was only small and simply of a secondary nature. 
In order to correct the want of the binding power of glycerine, 
if not wholly at least largely, the currier must seek to princi- 
pally neutralize its very great solubility in water. This can 
naturally not be done altogether without partially changing the 
nature of glycerine, and of course, also its softening effects. 
Still a better adherence of the glycerine to the leather can be 
brought about thereby. 

This may be effected in two ways. According to one, and 
doubtless the most practical way, a kind of artificial degras is 
composed with glycerine, by emulsioning it in a strong concen- 
tration, therefore as a very viscid substance with fatty bodies. 
As glycerine acts in a certain sense as a feeble alkali, similar to 



STUFFING LEATHER. 239 

a solution of potash, with which the degras is extracted from 
morocco-tanned skins, it can readily be rubbed together with a 
mixture of fish-oil and beef tallow, and emulsioned with it. 
The desired quantity of beef tallow is first dissolved in heated 
fish-oil, the mixture is well stirred together and permitted to 
congeal to a butter-like consistency. • To the soft mixture of 
fats is then added about one-quarter of its weight of glycerine, 
and intimately incorporated with it, so that the mass is finally 
of a cream-like condition. This glycero- degras enables the 
currier to obtain the same advantages as from lubricating with 
fat or glycerine alone. 

Glycerine may also be fixed in the leather by preparing it 
with substances which will dry out, and thereby lose their solu- 
bility in part, and, of course, neutralize this in a measure in the 
glycerine. For this purpose it might be recommended to mix 
glycerine with egg albumen, rubbing together, but always in 
such a proportion that the latter is present only in a very small 
quantity. This imparts to the non-drying glycerine a certain 
fixing basis, which again thereby preserves its greatest virtue 
of imparting suppleness. This prepared albuminous glycerine 
may either be used alone, or else serve as basis for the previ- 
ously-mentioned glycero-degras. 

In cases when such a trifling addition of albumen should 
appear too costly, glycerine may also be mixed with a small 
quantity of dextrine solution — an addition that is decidedly a 
defective one, still it answers its purpose to a certain extent. 

The combination of glycerine with tannin may also be re- 
garded as a special preparation. A corresponding quantity of 
extract of oak-bark or other tannin is by boiling dissolved in 
glycerine, which is easily done, and in this way it becomes a 
very valuable fat for lubricating the hide ; the good effects being 
still increased by emulsioning this tanninous glycerine in the 
above-explained manner with fish oil and tallow, and converting 
it into a degras. 

A practical method of stuffing with glycerine is described as 
follows : The leather is treated with a mixture of tallow, degras 



24O THE MANUFACTURE OF LEATHER. 

or fish- oil, and glycerine, instead of with the ordinary stuffing 
grease. As glycerine combines well with water, the stuffing is 
readily absorbed, and the glycerine very evenly distributed, 
which not only adds substance, but makes the leather excep- 
tionally soft. After the leather has been blackened, and while 
only partially dry, glycerine may again be worked into the 
grain side, followed by a coating of wax; this prevents the 
glycerine from working out on the surface and gives a drier 
feel. The method described gives a pleasing dull lustre to the 
leather. 

From the preceding it will be seen that although glycerine 
possesses certain advantages, it has also great defects, which 
can be corrected only by suitable preparation and admixture 
of other substances. 

TESTING OILS. 

Oils, degras, grease, etc., are difficult to judge, as to their 
real honest value. To those inexperienced in testing and tast- 
ing cod oils, etc., inferior goods are not much unlike the better 
grades. And it is well known that excellent leather may be 
spoiled and damaged in finish and appearance by the use of 
adulterated materials, skilfully compounded and sold at low 
prices which attract unwary buyers. 

There are few commodities sold in which adulteration is 
practiced more than in oils, as tanners and curriers know to 
their cost. We suggest the following simple tests : 

Apart from the test for determining compound oils, there 
appears to be no other except a chemical test, and that is un- 
satisfactory. To determine the amount of compounding, take 
a two-ounce vial and fill it half full of a very strong alkaline 
solution — ammonia, caustic soda or caustic potash. Fill the 
vial nearly full of oil and shake thoroughly. Mineral oil will 
not make soap, and will separate. Any animal or fish oil will 
mix with the alkali, and from its color can be told the com- 
pound and the percentage of the same. Neat's-foot oil will be 
yellow, but tallow and most other oils will be of different shades 



STUFFING LEATHER. 24 1 

approaching white. Lard oil will be whiter than tallow. The 
test will show sperm oil to be composed of about two thirds of 
paraffin oil. Lard oil is similarly adulterated. This test does 
not show the " stock " from which the oil is made, nor whether 
the animal acids have been extracted from the animal oils. 
These should have the acids extracted, which honest oil dealers 
now can do. 

The evil effects of the bad conditions of fats generally do not 
show themselves until the leather is finished and probably out 
of the hands of the tanner. The worst of these defects is the 
gumming and exudations due to the excess of acids in the oils, 
tallow or degras. The blame is not always due to the seller. 
The free acids increase in stored oils, and so it is quite possible 
that an oil which was of very good quality when bought may 
become almost worthless from excess of these acids by the 
time it is used. To distinguish a genuine degras from simple 
fat emulsions, the latter being generally sold at a higher price 
than the former, chemists nowadays generally resort to an esti- 
mation of the degras former. The most usual adulteration was 
found to be cheap wool fat, which if present in any quantity 
will give leather liquored with it a sticky feeling, which is the 
reason that wool fat cannot be used in tanning. In tallow the 
principal adulterant found is cotton-seed oil. Rancid tallows 
which spew out on leather are frequently found.* 

* For exhaustive treatises on all the oils, the reader is referred to the following 
books : 

Brannt. Petroleum : Its History, Origin, Occurrence, Production, Physical and 
Chemical Constitution, Technology, Examination and Uses; together with the Occur- 
rence and Uses of Natural Gas. Edited by William T. Brannt; Philadelphia, Henry 
Carey Baird ik Co., 1895. Price, #7.50. 

Brannt. A Practical Treatise on Animal and Vegetable Fats and Oils : Comprising 
both Fixed and Volatile Oils, their Physical and Chemical Properties and Uses, the 
Manner of Extracting and Refining them, the Practical Rules for Testing them ; as 
well as the Manufacture of Artificial Butter and Lubricants, etc. By William T. 
Brannt; second edition, revised, 2 volumes; Philadelphia, Henry Carey Baird & Co., 
1896. Price, $10.00. 
16 



242 THE MANUFACTURE OF LEATHER. 

BORAX. 

Borax, in addition to being used for softening water used in 
the soaks, and in the Teaches for extracting tannin, and for 
washing hides and skins previous to placing them in the tan 
liquor, is also employed for cutting the oils and fats used in 
stuffing leathers. Sal soda, chip, soaps, and soapine and other 
alkalies are also used for the same purpose. 

STEAM JACKET KE'JTLES. 

E. B. Badger & Sons, Boston, Mass., coppersmiths, manufac- 
ture steam jacket kettles and copper work of all kinds for the 
tannery and currying shop. 

STUFFING OR FAT LIQUORING WITH PALERMO FIG SOAP. 

Many tanners find great difficulty in properly stuffing or fat 
liquoring the leather after it is tanned. This is due to the fact 
that many people consider this operation a comparatively un- 
important one, believing that if the leather is properly tanned 
the subsequent processes will regulate themselves accordingly. 

This is a mistake, as the precipitation of fatty or oleaginous 
bodies in the fibre of the skin is an operation requiring as much 
judgment, skill and knowledge of materials used as any division 
in the complex art of leather manufacture. The great desider- 
atum in all fat liquors is a soap which will combine readily with 
the other ingredients and enter into combination with the min- 
eral salts, or tannins in the fibre of the skin, so as to render the 
finished leather soft, smooth and flexible without any traces of 
grease being left on the surface. 

Of the few soaps which possess this valuable property we 
know of none so well adapted to the stuffing of all kinds of 
grain leather as that manufactured by F. E. Atteaux & Co. and 
sold under the name of Palermo Fig Soap. 

This soap contains in itself all the properties of a good fat 
liquor, being rich in alkali without any excess of the same, and 
has the additional advantage of always being ready for use; 
thus dispensing with the labor of making up a fresh supply of 



STUFFING LEATHER. 243 

fat liquor for each batch of skins. Although it can be used 
as a fat liquor without any other ingredient, it also mixes 
readily with all the animal, fish and vegetable oils and also with 
egg yolk, and can be used in conjunction with them in any pro- 
portion. 

It imparts a fine, glossy finish to the leather and fills up the 
pores and nourishes the skin to an extent that no other soap or 
fat liquor can equal. It dissolves readily in boiling water and 
can be applied to the skins at a temperature of 125 F. 

FORMULA FOR MAKING FAT LIQUOR WITH PALERMO FIG SOAP. 

Put ten pounds Palermo fig soap in a clean barrel with just 
sufficient water to cover the soap. Apply steam and stir con- 
stantly, until the soap is thoroughly dissolved. Now add to the 
soap bath four gallons of neats'-foot oil or cod oil (first cut the 
oil with a few ounces of borax, potash or sal soda) . Stir for a few 
minutes until the oil and soap are thoroughly assimilated, then 
run in forty gallons of cold water to cool the emulsion. Then 
add ten pounds egg yolk and two pounds common salt. Stir 
the whole again, and apply to skins at a temperature of 75 F. 

Twenty gallons of this fat liquor is sufficient to fat liquor ten 
dozen skins. It should be added gradually to the skins, and 
the quantity used can be varied to suit the tanner's judgment. 
It will give excellent results on any description of light upper 
leather or glove stock. The proportions should be changed, 
however, when it is intended for use on heavy calf skins, in 
which case it would be well to add to the oil and soap bath five 
or six pounds of French degras, and the amount of egg yolk 
may be reduced to five pounds. 

In all cases care should be taken to cool off the soap and oil 
emulsion before adding the egg yolk, in order to prevent coag- 
ulation of the albuminous constituents of the egg which would 
result if the latter was added to water of a higher temperature 
than 75 F. 

FAT LIQUORS. 

It is hard to answer the query of "What is the best fat 



244 THE MANUFACTURE OF LEATHER. 

liquor for chrome tanned leather?" as hardly any two manufac- 
turers use the same formula. All the dealers in oils and fats 
have a fat liquor of their own make. The Martin Dennis Chrome 
Tannage Company, Newark, N. J., also make and sell a speci- 
ally-prepared fat liquor, under the name of " Chromol." Some 
manufacturers have trouble in obtaining an even color on their 
skins — as they are spotted in places in the color. 

There are various causes for this, but generally the fault lies 
either in the animal grease not being taken out or in too much 
fat liquoring. One of the most successful tanners, whose leather 
always shows a superior face and grain, sends all his skins after 
being blacked to a concern who take out grease by the naphtha 
process. Some manufacturers use a bath of water and borax 
for the same purpose. On receiving them back they are staked 
and recolored. 

CHROMOL FAT LIQUOR FOR CHROME TANNED LEATHER DIRECTIONS FOR USE. 

Chromol may be warmed as it is and used as a hand stuffing 
for heavy leather ; or may be dissolved in any proportion of 
warm water and used as a fat liquor, and milled into the leather 
by means of a pin mill drum. 

Chromol imparts great softness, pliability and strength to 
the chrome leather without rendering the leather in the least 
greasy or gummy. 

One special and desirable feature of this preparation is that 
it may be used on all fancy light colors without spotting or 
streaking the leather, a fact which commends it as a substitute 
for egg yolk. 

For glove leather it is sometimes desirable to make a batter 
of flour and water and then add the chromol to the batter, and 
knead or mill the skins in the mixture. 

WATER-PROOF STUFFING. 

A good water-proof stuffing can be made as follows : Two 
and one half ounces of good drop black or vegetable black well 
ground in any suitable oil, ten ounces of castor oil, French sec- 
ond pressing, and eight ounces of tallow. 



STUFFING LEATHER. 245 

WATER-PROOFING LEATHER. 

The process of rendering leathers water-proof, or impene- 
trable to water, has formed the subject of many patents ; but 
with the exception of rendering leather impervious to water by 
the aid of mineral salts, we have not met with any compound 
that perfectly water-proofs leather, whether upper or sole, ex- 
cept the following : 

As regards the mineral process, the formation of sebate of 
alumina or of iron in the leather, by first steeping the leather 
in a solution of soap and then in one of either of the above 
salts, has never yet proved its full title to be a perfect water- 
proofing process ; and also the process of rendering gelatine 
insoluble in the pores of leather by means of an astringent, as 
alum, does not perfectly fulfill all the conditions necessary for 
rendering the leather so treated impervious. 

As regards stuffing componds, which depend for their effic- 
iency in filling the pores with some body, such as resin or wax, 
antagonistic to water, those compounds are far from good, be- 
cause those of such compounds that cannot be extracted from 
the leather by heat may be eliminated by means of alkalies, 
which, by saponification of the resin or wax, render these bod- 
ies miscible in water. Compounds in which resin is the solid 
compound for filling up the pores of the leather to make it 
water-repellent can be converted into a miscible compound by 
means of sodic hydrate, while those compounds which depend 
for these water-proofing qualities on the wax as a component 
can be similarly treated by means of borax or borax and am- 
monia. 

One of the most favorite compounds for giving leather the 
quality of water-resisting is paraffin wax, either driven into the 
leather by means of heat, or else by means of a solvent, as 
naphtha, benzine or carbon disulphide. But this wax can also 
be extracted again from the leather by either of these means ; 
and if it be upper leather thus water-proofed, the lining of the 
boot made therefrom will become saturated with the wax if the 
boot be held in front of a fire; and again, if a spontaneous 



246 THE MANUFACTURE OF LEATHER. 

solution of this or any other wax be used to impregnate sole 
leather, the wax will be eventually driven out of it by the pres- 
sure on the sole when the leather is made up into boots. 

After trying some scores of formulae for producing water- 
proof leather, we can find nothing better than these two. For 
sole leather : Warm the leather if it is oak or hemlock tanned 
and heat it if it is mineral tanned and brush it with a coat of 
copal or amber varnish ; an oil varnish is better than a spirit 
varnish, as the former is more flexible, while for upper leather 
nothing is superior to this compound : 

1 part by weight of raw gutta percha, 

1 part by weight of paraffin wax, 

2 to 3 parts by weight of benzine. 

The gutta percha should be the raw, brown kind, not the vul- 
canized or colored kind. 

To make this mixture, put the ingredients into a jar lightly 
covered with a plate and place this vessel near some source of 
heat where it will be very gradually raised to a warm tempera- 
ture, but not enough to cause the benzine to vaporize, ignite or 
explode. Be very careful about explosions. After the solids 
have dissolved, stir the mixture and then, having rendered the 
leather warm, brush it with this solution, or else steep the 
leather therein until well impregnated, and then hang up to 
dry. 

The compound, if properly prepared, will set semi-solid, and 
only requires to be reheated for use as above. 

The advantage of this compound is this : Both the wax and 
gutta percha enter the pores of the leather in a finely-divided 
state and fill them up, while the volatile solvent eventually 
evaporates out of the leather, leaving the solids therein ; now, 
neither of these bodies, wax or gutta percha, can be completely 
eliminated from the pores of the leather, because they are so 
thoroughly combined and in such a fine state that an alkali 
would fail to saponify the wax, and heat would fail to drive it 
out, because the gutta percha is worked in by the alkali, and 



STUFFING LEATHER. 247 

being so intimately impregnated in the pores, it is next to im- 
possible to drive it out by heat; moreover, the gutta percha is 
a flexible body. And then this mass is an excellent stuffing 
compound for curriers' use in preparing water-proofed wax 
calf, satin hide, pebble grain, etc. 

The author of the above says : 

" I have tried this water-proofing compound on a score of 
different kinds of leather, and never found it to fail in rendering 
them absolutely impervious to water ; and, moreover, so water- 
repellent that the leather will float in water for hours, sufficient 
proof that no water enters the pores; both these solid bodies 
are unacted on by alkalies, and thus I believe I can claim for 
this compound (one, by the way, which I have formulated after 
much research) the quality of being a perfect water-proofing 
compound, 

"As regards colored leathers — tan, morocco, etc. — I advise 
one application only applied to the flesh side lightly, not suf- 
ficient to stain the leather through ; but for upper leathers (kid 
excepted), the leather may be steeped in the compound, and 
wiped free of all superfluous drippings." 



CHAPTER XVI. 

SETTING- OUT. 

The method of setting-out described in the preceding chap- 
ter is not suitable for all classes of leather, but is for kips 
and skins or other light leather. Heavy leathers, such as 
harness and belting leathers, require a considerable amount of 
labor in setting, and it must be done in suitable condition if it 
is to be properly done. When available, the setting machine 
may be successfully used if skilfully applied, but in applying 
the same care must be taken not to distort the pattern of the 
hide, otherwise it will take the men who reset after the machine 
as long to regain a good pattern as the machine has saved ; 
nevertheless, as above said, if the machine is skilfully applied it 
may be advantageously used in doing the most laborious part 
of the work. 

The machine shown in Fig. 61 is built by the Vaughn 
Machine Company, Peabody, Mass., and is for stoning-out, 
scouring and setting-out, and is intended to be used for glove, 
satin and oil grain, wax and split leathers, etc. 

This machine will remove the wrinkles from the neck, and 
will in every way smooth out and thoroughly prepare the 
side or hide for the belt knife leather-splitting machine. 
In fact it is invaluable for stoning-out rough leather for the 
leather-splitting machine, and far better results are obtained 
with it than can be had in any other way. The machines 
shown in Figs. 39 and 83 are also used for stoning-out ; but 
the machine shown in Fig. 61 is used for large products of 
leather. 

( 248 ) 



SETTING-OUT. 



249 





CHAPTER XVII. 

WHITENING AND SHAVING LEATHER. 

The side having been stuffed and next " set out " (which 
latter operation can be performed for calf-skins or the heavier 
grades of upper leather by the machines shown in Figs. 58, 59 
and 60), the next step in the pro- 
cess of manufacturing upper leather 
is that of whitening. This is usually 
accomplished by one of three ways : 
The leather may be placed on a 
table and whitened with a slicker, or 
cut over with a currier's knife on a 
beam, or the whitening can be per- 
formed by machinery. 

Fig. 62 shows the French pattern of whitening slicker, which 
is the kind usually employed in this country. The blades, 
which are of cast steel, are usually of two degrees of hardness ; 
the bright blade compares in temper with a medium hard blade, 
the half polished are softer, being of a lower temper. 

Fig. 63 shows the form of beam now generally employed in 
currying shops. The beam-bed and face are adjustable by 
means of screws, and the beam may be elevated or lowered at 
any necessary height to suit the convenience and comfort of the 
workman. The faces may be either of lignum vitse or of glass. 

There is a great variety in the construction of currier's 
knives ; but the form shown in Fig. 64 is the most common. 
The blades are screwed in the brass jaws by three screws from 
each side, thus securing equal strength. The blades for the 
currier's knives are made of hammered steel, and are either 
bright or unpolished, and vary from seven-eighths to two inches 

(250) 



WHITENING AND SHAVING LEATHER. 
Fig. 63. 



251 



J 



i f 

mm 




Fig. 64. 




In width, and those kept in stock by the manufacturers are 
made in nineteen and twenty gauge, but other gauges are 
manufactured to order. 

UNION WHITENING AND BUFFING MACHINE. 

The Union Whitening and Buffing Machine, made by J. T. 
Freeman & Co., Woburn, Mass., is based upon the patents 
granted to Oliver C. Smith, of Ipswich, Mass., several later 
patents having been granted to J. T. Freeman et al. for improve- 
ments. 



252 



THE MANUFACTURE OF LEATHER. 



The machine for whitening and buffing leather invented by 
Oliver C. Smith is shown in Figs. 65 to 68. 

Fig. 65. 




Fig. 66. 




Fig. 67. 




Figure 65 represents, in top view, a machine embodyiug 
Smith's invention ; Fig. 66, a longitudinal vertical section 




WHITENING AND SHAVING LEATHER. 253 

thereof on the dotted line x x, the table or bed being shown in 
elevation. Fig. 67 is an enlarged detail, 
partially in section, showing the boxes of 
the sliding frame ; and Fig. 68, a section 
of Fig. 67 on the dotted line y y. 

In this invention the pulley A is fixed 
directly upon the crank-pin k, joining the 
two cranks i k, projected from the shaft 
B. The weight of the pulley A is coun- 
terbalanced by the weight C, one on each 

crank. The belt u on this large fixed pulley A is extended 
over the pulley / on the shaft a 2 at the upper end of the usual 
swinging frame, and rotates the said shaft, together with its 
pulleys s, which by small belts r revolve the rotary cylinder or 
tool/ in the usual manner as the link g, herein made double, 
reciprocates the carriage D on the guide-rods c. This carriage 
is composed of yokes 20, 21, connected by a bar, 22, the yokes 
having depending from them bearings a 3 to receive the shaft a 2 , 
which turns in the said bearings. The boxes which run on the 
guide-rods c have Babbitt or other linings, E F. Upon the lin- 
ing F, the inventor has placed an adjusting-wedge, G, provided 
with one or more inclined teeth or wedging-surfaces, 9, and 
above the adjusting-wedge he has placed a cap, I, having at its 
under side one or more opposed teeth or inclines, 8. 

The machine, as at present built by J. T. Freeman & Co., of 
Woburn, Mass., is shown in Fig. 69. 

This is the only machine ever put on the market that will 
whiten and buff successfully. It works the same on stuffed, 
greased or dry leather. It does the work equally as well as can 
be done by hand and takes off no more stock. It turns off a 
large amount of work and requires but a short time for an 
operator to learn to run it. Since purchasing the patents and 
patterns of the above machine J. T. Freeman & Co. have made 
a large reduction in the selling price of it and have placed it at 
a figure in reach of all leather manufacturers, in fact where 
they cannot afford to be without them. The machine occupies 
a space of about 10x5 ft. and is driven by a six-inch belt. 



254 



THE MANUFACTURE OF LEATHER. 
Fig. 69. 




UNION WHITENING AND BUFFING MACHINE. 

This machine is almost indispensable in a leather finishing 
shop, in fact we know of few machines which are so desirable 
and profitable. 

SHAVING MACHINE. 

Fig. 70 shows the Rood improved shaving machine, manu- 
factured by the Vaughn Machine Co., Peabody, Mass. 

This machine is guaranteed to be a first-class machine in 
every respect for shaving the alum, acid and combination 
tannages. These machines are successfully used by the leading 
manufactures in shaving kip, calf, goat and sheep, and are 
acknowledged to do superior work to any machine or hand- 
work, and is used now almost exclusively for shaving by all 
manufacturers of leather. 

The side frames and braces are planed and bolted together, 



WHITENING AND SHAVING LEATHER. 



255 



and are supported by a heavy bed-frame, thus making it im- 
possible for the working parts to wear unevenly, by the work- 
ing of the side-frames, owing to an unsteady floor. 

Fig. 70. 




ROOD SHAVING MACHINE. 



The cutter is a new departure from all others now in use. 
The blades meec in the centre of the cylinder, and each pair 
have an extra cutter that cuts out the centre in advance of each 
other, thus allowing them to enter the skin to the depth of the 
cut they are to take. 

With this improved cutter cylinder, the Rood shaver is able 
to shave the best quality skins and give the desired soft finish. 



CHAPTER XVIII. 



BLACKING LEATHER. 



The side of leather having passed through the previously 
described operations, and been last boarded is now in the state 
for blacking, and this is performed either by hand or machinery. 
It is thought by manufacturers that the hand process is pre- 
ferable for the heavy grades of upper leather ; but upon what 
ground it is not plain, as some of the machines constructed for 
this purpose are models of mechanism, and perform the work 
much more economically and thoroughly than is usually done 
by the hand process. 

Figs. 71 and 72 show the two forms of blacking brushes in 
common use, and they are made both soft and stiff; the best 
quality are extra copper-wired, and are all bristle. The 
oval form is always made with a strap ; but the round form 
has either handles or straps. Both brushes are made in first 



Fig. 71. 



Fig. 72. 





and second qualities ; but it is economy to purchase the best 
made, as the extra wear more than compensates for the small 
difference in price. 

Brushes for blacking leather are made in both the oval and 
round form by the Vaughn Machine Co., Peabody, Mass. 

(256) 



BLACKING LEATHER. 



257 



batchelder's leather blacking, coloring and dressing machine. 

Figs. 73 to 85 show the leather blacking, coloring and dress- 
ing machine patented by Batchelder, and built by the Vaughn 
Machine Co., Peabody, Mass. 

Fig. 73 is a left-hand-side elevation of a machine embodying 
Batchelder's invention ; Fig. 74, a front view thereof, with the 
table 11 omitted; Fig. 75, a longitudinal vertical section of Fig. 
74 ; Fig. j6, an enlarged detail to be referred to ; Fig. yj, a 
detail in top view of Fig. 76, with the brush c omitted, and Fig. 
78 is a modification to which reference will be made. 

Fig. 73. 




This machine will also black grain leathers and season oil 
skins. 

The blacking or liquid dressing, or material to be applied to 
the upper surface of the hide or skin, B, is placed in the recep- 
tacle e, which is shown as an open box, the sides of which, at 
its lower end, are concaved, to fit the periphery of the recep- 
tacle-roller e', which may be made to travel near the straight 
lower edge, 2, of the bottom of receptacle by means of the ad- 
justing screws e 1 , the amount of space between the edge of the 
bottom of the receptacle e and the roller e' determining the 
~ 17 



258 



THE MANUFACTURE OF LEATHER. 
Fig. 74. 




JUL JH_ 



Fig. 75. 




Fig. 76. 



Fig. 77. 




1 


m 1 iiia mi 


:i 1 


■ i' J 'g-i J 


r 




! a-z* ^ 




« 


1 * * J 


[Lli-Lbd! 


J 1 




BLACKING LEATHER. 259 

amount of blacking or dressing to be delivered to the brush c. 
The roller e' may be driven more or less rapidly to carry or de- 
liver more or less blacking or dressing to the brush 

Fir *7$? 

c. This may be done by changing the size of the ^ c 

gear e 3 on the journal of the roller e', the toothed 
speed-wheel f, which engages the gear e 3 and drives 
the roller e', being mounted on a stud of an ad- 
justable carrier,/ 7 , provided with a locking device, 
ft 2 , to engage an arch, ft 3 , and hold the carrier in proper position. 

It is preferable to slightly groove, flute, or pit the roller e' , to 
enable it to take up a greater quantity of blacking or dressing. 
The hide or skin as it leaves the supporting-surface a* is deliv- 
ered upon an endless belt or moving bed,^", shown as composed 
of cords or tapes extended about rollers g' g 1 , the one g* being 
driven positively from the toothed wheel b by the intermediate 
worm, h, which engages the pinion h' at the end of the shaft g' . 
The tanned hide or skin to be dressed is introduced between 
the supporting-surface of and roller or brush c under a roller, /, 
which, as clearly shown in Figs. 75 and j6, has its journals 
mounted on levers or arms /', pivoted at / 2 and acted upon by 
springs I 3 , to keep the roller depressed upon the hide or skin to 
properly hold it. The front ends of the levers or arms I' are 
joined to a holding-bar, m, which is of a shape to fit the space 
between the brush c, the support <z 4 , and roller /. The under 
side of this holding-bar (see Fig. 76) is so shaped, curved, and 
located with relation to the surfaces of the roller / and the sup- 
porting-surface a* as not to bear upon the hide or skin until 
after the passage of the edges of the same beyond the nip of the 
roller /, the holding bar being devised to act upon and hold the 
end of the hide or skin, after passing beyond the nip of roller / 
(the latter then dropping), and prevent the hide or skin being 
drawn in too rapidly. In front of the apparatus there is placed 
a table, n. 

In some instances and for some classes of work the inventor 
modifies the machine so far described, as represented in Fig. 
78, and where there is shown the roller / as elevated consider- 



26o THE MANUFACTURE OF LEATHER. 

ably above the position shown for it in Figs. 75 and j6, and 
in such position there will be left sufficient space to permit the 
operator to retain hold of and control the position and move- 
ment of the hide or skin being acted upon by the brush or rol- 
ler c, and in such case also the holding-bar m is omitted. 

To prevent the blacking or dressing being thrown from the 
brush or roller c toward the front of the machine there is pro- 
vided the auxiliary spatter-guard 0. The roller / and the holder 
m, when used, also serve to prevent the blacking or liquid 
dressing from being thrown out at the front of the machine. 
The supporting-surface a 4, and brush e are as long as the maxi- 
mum width of the hide or skin to be blacked or dressed ; but as 
the hides or skins being finished or dressed are always different, 
both as to width and outline at their edges, it results that the 
brush c always applies blacking or dressing to more or less of 
the surface #*. 

The blacking or dressing applied to the surface of must all 
be removed and the surface left clean so as not to apply 
blacking or dressing to the under side of the hide or skin as it 
comes in contact with it. To do this the inventor has provided 
a wiper or cleaner,/ (shown clearly in Figs. 74 and 75), as a 
strip of flexible material held by a suitable adjustable bar, p l , 
so that the edge of the wiper or cleaner may be pressed with 
more or less force against the surface ct, the degree of its pres- 
sure being preferably regulated by adjusting-screws/ 3 , The 
material wiped or scraped from the surface « 4 drops into the 
trough q and passes therefrom into a suitable pail or bucket to 
be rinsed, if desired. 

By driving the brush-roller c and the supporting surface « 4 
independently, the inventor is enabled to rotate either at any 
desired speed, and thus rub the blacking, coloring, or dressing 
matter more or less into the surface of the hide or skin. 

The bearings for the brush c and roller e' will preferably be 
made adjustable vertically to accommodate for the thickness of 
the leather and compensate for wear. 

Batchelder in 1883 patented an improvement on the machine 



BLACKING LEATHER. 



201 



just described, which improvement is shown in Figs. 79 to 82. 
In the machine described in Figs. 73 to 78, the brush-roller 
which applied the blacking or the liquid dressing to the leather 
on a rotating supporting surface or roll had its bristles set 
radial ; but with such a brush the distribution of the blacking 
is not so uniform and thorough as is desirable ; so to cause the 
brush to apply the blacking to every minute part of the face of 
the leather being blacked or treated, Batchelder has inclined 
the bristles of the alternate rows of bristles of the brush in dif- 



Fig. 79. 






ferent directions, those of one row inclining toward one end of 
the cylinder and those of the next alternate row toward the 
opposite end of the cylinder, so that the ends of the bristles, 
besides traveling over the leather in the direction of rotation 
of the brush-roller, also, when in contact with the leather, spring 
or yield in opposite directions, the free ends of the bristles of 
alternate rows moving in opposite directions longitudinally as 
compared with the axis of the brush-roll, thus working the 
blacking backward and forward across the leather, as well as in 
the direction of its movement over the supporting-surface. In 



262 THE MANUFACTURE OF LEATHER. 

this way every particle of the upper side of the leather is effec- 
tually blacked and streaks are effectually prevented. 

Fig. 79 represents in section a sufficient portion of a leather 
blacking or dressing machine to illustrate the present improve- 
ment; Fig. 80, an end view of the brush-roller on a larger 
scale; and Figs. 81 and 82, two partial sections thereof in the 
dotted lines x andjj/. 

The supporting bed a*, color-roller e', deflector d, spatter - 
roller b' and roller i are as in the machine shown in Figs. 73 to 
78. The roller c, which applies blacking to the leather B, has 
its alternate longitudinal rows of bristles a b inclined in oppo- 
site directions, those of one row being as in Fig. 81, and those 
of the next row as in Fig. 82, so that as the bristles yield on 
coming in contact with the leather B those of one row, as in 
Fig. 81, will yield and move toward the left end of the brush - 
eylinder, while those of the adjacent row (see Fig. 82), oppo- 
sitely inclined, will move toward the right of the cylinder, the 
bristles of the two rows thus moving over the leather one after 
the other in opposite directions, in the direction of the length 
of the supporting roller « 4 , at the same time that all the bristles 
sweep over the leather as it is carried under it by the roller a 4 . 
In this way the blacking is brushsd on the leather both longi- 
tudinally and transversely. The brush- cylinder has a metal 
journal at each end, the journal preferably forming part of a 
metal shaft extended through the cylinder c of wood. The cyl- 
inder c is provided with a series of diagonal holes at opposite 
inclinations (see Figs. 81 and 82), into which the bristles a b 
are inserted and held by glue and wooden plugs or galvanized 
nails, or in any usual manner. 



CHAPTER XIX. 

MACHINES FOR ROLLING, PEBBLING, GLASSING OR POLISHING, 

FINISHING, ETC. 

The leather after being properly blacked is next submitted 
to one of the finishing processes, and while this operation is 
sometimes performed by hand, still by far the greater part of 
the leather curried in this country is glassed by machinery, and 
a large number of contrivances have been invented for this pur- 
pose, as well as for pebbling, finishing and similar operations. 
The scarcity of labor in all the Northern States from the com- 
mencement of the late war of the rebellion, and the enormous de- 
mand for leather which immediately arose, stimulated inventors 
in all lines of leather production, and machinery for this purpose 
which came into use from i860 to 1873 is still the kind that is 
now commonly employed with many improvements in all sec- 
tions of the country. 

The glazing machine was one of the first steam-driven tools 
introduced into the trade. It was, at first, thought it would do 
away with hand-glazing entirely, but subsequent developments 
proved that it could only be utilized upon the heavier grades of 
stock. 

The present machine, however, is a vastly improved and 
much more delicate piece of mechanism, to which the finest 
grades of stock can be entrusted without fear of its being burnt 
or torn into fragments. 

In Fig. 83 is shown an illustration of the Bowers Rocker- 
Motion Leather Finishing Machine, made by Albert M. Bowers, 
Newark, N. J. 

This machine is now largely used for glazing, rolling, peb- 
bling, stoning, brushing and finishing leather, and it is an im- 

(263) 



264 



THE MANUFACTURE OF LEATHER. 
Fig. 83. 




4f */* 




BOWERS ROCKER-MOTION LEATHER FINISHING MACHINE. 

provement over other modes of finishing leather in the method 
of construction over other machines. 

The rocker motion insures economy of power, the rocker be- 
ing the segment of the circle, while other machines are made 
with a slide or pendulum, or with a link motion, and the 
adaptation of the rocker as a resisting power removes all fric- 
tion possible. At the same time it insures the machine to run 



MACHINE FOR ROLLING, PEBBLING, ETC. 265 

without heating and without flinging oil upon the leather while 
it is in operation, two very important factors, as a spot of oil 
upon fancy leather would spoil the whole skin. 

Mr. Bowers also gets great power for rolling and pebbling. In 
the construction of the machine, the larger part is wood. The 
wooden part, being the resisting part, is in direct sympathy 
with the leather, and while the machine could be built of 
iron, yet machines built of iron, Mr. Bowers claims, are too 
rigid in practice to work upon leather, having been demon- 
strated many times upon the same kinds of leather. There- 
fore this machine takes the lead of other machines for like pur- 
poses, and is a studied improvement over first machines 
manufactured. 

With it, it is also possible to stone out hides preparatory for 
the splitting machine. All kinds of leather, the whole hide or 
the sides, sheep skins, goat skins, skivers, bag leather, and all 
kinds of leather that are made to imitate natural grains, can be 
pebbled with it. In glazing, it will glaze every kind of leather 
to the greatest success. It will glaze the whole hide, the sides, 
sheep skins, skivers, goat skins ; is used for glassing, shoe grain, 
polish leather, bag leather, harness leather, brush backs, hat 
sweats, on cloth and paper imitations of leather, on the thinnest 
buffings. Will glaze the different shades of colored leather to 
perfection, being free from danger to fling oil upon colored 
leather. It is used for glassing out suspender leather, insole 
splitts, buffings, heavy belt leather, and in fact it is used on 
every kind of leather that is required to be glazed. 

Used also for rolling shoulders and trimmings, calf-skins for 
pocketbook stock in all its branches, for glazing alligator, lizard 
and snake skins, and has been subjected to the severest trials, 
and most arbitrary requirements. Over 1775 of these machines 
are in operation to-day. 

It is also being extensively used in pocket-book factories to 
glaze the small pieces of stock after having been cut into the 
different sizes and shapes for pocket books, after the edges have 
been shaved to restore the gloss to the pieces from finger-marks 
and other handling. 



266 



THE MANUFACTURE OF LEATHER. 



The improved iron glassing jack, made by J. T. Freeman & 
Co., Woburn, Mass., is shown in Fig. 84. 




IMPROVED IRON GLASSING JACK. 



This is a self-contained machine, all of iron and steel but the 
table. It has no posts or braces, and the peculiar construction 
of the frame insures great rigidity and consequent effectiveness. 
It is so constructed that the pressure can be regulated by a 
small hand-wheel in front of the bed. There is also a bolster 
stretcher attached to lower end of the bed, to draw up the 
stretch of the bolster. The machine requires no special setting 
up, as it is shipped altogether on a wooden base ; all that is 
necessary is to level up same and bolt firmly to the floor. The 
manufacturers guarantee this machine to work equally as well 
on the paste or black ; also on buff, harness or belt leather. 

Fig. 85 shows the improved straight bed rolling or pebbling 
jack made by J. T. Freeman & Co., Woburn, Mass. 

Owing to the increased demand for a straight bed pendulum 
machine, and being desirous of having a jack of a different con- 
struction from any other manufacturer, the builders designed 
the above machine. The bed of this jack is perfectly straight ; 
the arrangement under the bed is the same as a pair of scales, 
thus giving an equal pressure on all parts of the stroke, and has 



MACHINE FOR ROLLING, PEBBLING, ETC. 



267 



only one small spring in the center. It is a very heavy ma- 
chine and works equally as well on light or heavy stock. The 
builders have given this machine a thorough trial and feel safe 
to say that it is second to none on the market. 

The anti-friction roll made by J. T. Freeman & Co., Woburn, 
Mass., is especially adapted for heavy work, also on colored 
leather and skins. It requires no oil, and thus overcomes all 



Fig. 85. 




IMPROVED STRAIGHT BED ROLLING OR PEBBLING JACK. 

grease-spots on the leather. The makers will guarantee it not 
to heat or burn the leather, but to warm up just enough to give 
a good bright polish on the stock. Rolls can be furnished to 
fit almost any rolling or pebbling jack. 

martin's improved machine. 

Martin's improved machine is shown in Fig. 86. 

It is built by William F. Martin, Salem, Mass. 

For simplicity of design, compactness, easy and silent action, 
facility of adjustment, quantity and quality of the work it will 
perform, and the high rate of speed at which it can be operated, 
it needs only to be examined to commend itself to every one 



268 THE MANUFACTURE OF LEATHER. 

Fig. 86. 



martin's improved machine. 

using machinery in all the branches of the leather-finishing in- 
dustry. 

In currying it will "set out" pebble, " stone out," "glass in 
black and paste," using either oil or soap blacking, entirely 
without hand labor. 

For the morocco or lining finisher it will glaze, roll, pebble 
and glass out, doing a quality of work equal to any machine 
now in use. 

THE KNOX IMPROVED INCLINED BED LEATHER FINISHING AND 
PEBBLING MACHINE. 

In Fig. 87 is shown an illustration of the Knox improved in- 
clined bed leather finishing and pebbling machine, built by the 
David Knox & Sons Machinery Company, Lynn, Mass. This 
machine can be used for finishing and pebbling all kinds of 
leather. 

A medal and diploma were awarded these machines at the 
Centennial Exhibition for " excellence of work done, sim- 
plicity and durability of all parts, and for the little power 
needed to operate them, and ease in adjusting and running 
them, they stand beyond all question unrivaled." The frames 
have been re-designed, adding greatly to their strength and 



MACHINE FOR ROLLING, PEBBLING, ETC. 

Fig. 87. 



269 




THE KNOX IMPROVED INCLINED BED LEATHER FINISHING AND PEBBLING MACHINE. 

rigidity. All these machines are now furnished with the new 
slotted balance-wheel, having an adjustable stroke from 16 to 
32 inches, and making a very easy and smooth-running motion. 
The outside bearings recently put on give great steadiness and 
smoothness to the motion of these machines. 

Patents have been granted for improved adjustments for the 
bed. Besides giving a range of nearly three inches for raising 



270 THE MANUFACTURE OF LEATHER. 

the bed, the adjustment for regulating the tension of the springs 
is absolutely separate from and independent of that raising the 
bed. This allows the most perfect and delicate adjustments 
to be accomplished with ease and facility. 

These machines are used in polishing, glazing, dicing and 
pebbling all grades of leather with the same remarkable success, 
from the lightest French kid to the heaviest currier's work. The 
best evidence of the value of these machines is shown by the 
increased sales during the past five years, and the large num- 
ber used by the leading firms in this country, many running 
constantly from five to fifteen machines. 

An extra wide bed, carrying a strap six inches wide, is 
especially adapted for currier's work. 

The Company also makes an improved level bed bottom fin- 
ishing and pebbling machine. They claim for these machines : 

First: Great strength and rigidity of frame — qualities in which 
they excel all other machines made. 

Second : That these machines are complete in themselves — 
not havfng any of their working parts attached to or depending 
on the building, and well-balanced in all their movements, so 
that in running at any speed, they will not rack or injure the 
building. 

Third : A range and ease in adjustment possessed by no other 
machine. 

Fourth : That the adjustments for the bed are simplicity 
itself, and are independent of each other. They are all within 
easy reach of the operator, who has the machine under com- 
plete control without changing his position for glazing. The 
whole bed can be instantly dropped one-half inch, clear of the 
tool, and as quickly raised into position for work. This allows 
the machine to be run all the time without any useless wear on 
the strap, a very important feature, for which the Company has 
patents pending. 

Fifth : That there is absolutely no wear-out to any of the 
working parts of the bed, and no possibility of its getting out of 
order by the work. 



MACHINE FOR ROLLING, PEBBLING, ETC. 27 1 

Plain and figured agates, glasses and flints, leather, wood and 
fibre straps, smooth and pebbling rolls of all kinds furnished to 
order. 

Fig. 88 shows the celebrated Coombs Pendulum Jack made 
by the Vaughn Machine Company, Peabody, Mass. 

Fig. 88. 




COOMBS PENDULUM JACK. 

What the manufacturers claim for it is : 

First: That it is all iron and steel except the face of the bed. 
It is all contained in one frame, and consequently cannot get 
out of line, there being no wood to shrink and become loose. 

Second : That we use a straight bed, which gives the opera- 
tor better control of the leather and does not wear out the bol- 
ster, as the curved bed does. 

Third: That our jack will run 25 per cent, easier than any 
other jack doing the same work. 



272 THE MANUFACTURE OF LEATHER. 

Fourth : That it is heavier, stronger and more durable, be- 
ing made of the best material and in the most workman-like 
manner. 

Fifth : That the arrangement of the bed is entirely new, and 
is the best that has been produced by any one so far. The 
reason is this, that you can get an absolute even pressure all 
over the bed and more elasticity than on any other machine. 
You can also have perfect control of the bed from the front 
of the machine, one screw raising or lowering both ends of the 
bed at the same time, and one screw regulates the pressure for 
both ends of the bed. There are also two other screws to ad- 
just the bed to any desired position. 

Sixth : That our jack can be run with less repairs, as all the 
bearings are babbitted, and the boxes have caps to take up the 
lost motion. 

Seventh : That our machine occupies the least possible space, 
the height 7 feet 10 inches, the floor space 6 feet by 7 feet. 

This machine is designed especially for printing, or any heavy 
work. The manufacturers build this machine lighter to do 
glassing and polishing. 

They also make and cut pebbling rolls of any pattern desired. 



CHAPTER XX. 



STAKING MACHINES. 

The "hand-method " staking machines (shown in Fig. 89), 
built by F. F. Slocomb & Co., Wilmington, Del., is now fitted 
where required with a swivel pressure adjustment of novel de- 
sign, which is claimed to be far more practical and exact than 
any prior device for the purpose. Other recent improvements 
enable this machine to stake successfully many classes of work 

Fig. 89. 




" HAND -METHOD " STAKING MACHINE. 

heretofore either impossible to do on any machine or else in- 
differently done. Among these may be mentioned several 
varieties of fine glove leather, fine kid, alum, sheep and lambs, 
etc., and chrome tanned skins generally. On kangaroo and 
kangaroo calf, etc., and Russia calf, the firm state that their 
improved combination padding and staking jaws of leather and 
felt will surprise users by the fine quality of work done. In 
addition they have two other sets of staking jaws, all different 
and giving different results, thus fitting one machine to do 
many lines of work by merely changing the jaws. The ad- 
vantage of this has been shown many times over in factories 

18 (2 73 ) 



274 THE MANUFACTURE OF LEATHER. 

where any change in tanning or finish has occurred. Ma- 
chines are built in four sizes, suitable for any work, from lamb 
skins to whole hides. 

This machine takes the place of knee or arm staking and pad- 
ding on light work, and soft boarding on heavy work. 

The staking machine is a marked improvement over the 
hand stake. This latter was not used in the morocco branch 
of the trade until the dawn of the present era of chrome tan- 
nage. It was an upright wooden stake, some two feet in 
length and eight inches in width, into the tapering top of 
which was fixed a broad steel blade. The skin was drawn 
across this blade, the weight of the workman's body being 
thrown upon it. Great care was exercised in order to guard 
against cutting the skin ; should this occur, the staker's bal- 
ance would be lost, and he would be in danger of being impaled 
upon his stake. 

The staking machine accomplishes the work of a half dozen 
hand stakers. There are several makes in use, and improve- 
ments are constantly being added. 

The staking machine shown in Fig. 90 is built under the 
Stakpole patent by the Vaughn Machine Co., Peabody, Mass., 
and it successfully meets all the requirements of the morocco 
and light leather trade. The leather is staked with the grain 
side up, so the operator sees just what is being done through 
the whole operation. 

The tension is instantly applied or released by hand or foot, 
and the jaw with its flexible fibre pad cannot be equaled by 
any other device for this work. 

It will take out the stretch in the leather thoroughly, softens 
perfectly and no damage or tearing. No danger of grease 
spots or soiling in the least any fancy colored stock. 

Floor space required, only 43^ ft. x 3 ft. Simplicity of con- 
struction and operation. Self-contained and no jar or noise 
perceptible when it is in operation. Minimum of power re- 
quired, a two-inch belt will run it. Maximum amount of work 
obtained. 



STAKING MACHINES. 
Fig. 90. 



275 




STAKPOLE STAKING MACHINE. 



Fig. 91 shows the staking machine built by Wm, F. Martin, 
Salem, Mass. It can be adjusted to any kind of leather, in- 
cluding napa. For napa an extra tool is required for spread- 

Fig. 91. 




MARTIN'S STAKING MACHINE. 



276 THE MANUFACTURE OF LEATHER. 

ing out the leather, and it is furnished by the manufacturer 
when required. This machine is unexcelled on calf, kangaroo, 
chrome, Russia calf and glove leathers. It is noiseless in 
action and is run by a smaller amount of power than any other 
staker on the market. Pressure can be adjusted while the 
machine is in operation. 

Staking machines are also built by Geo. W. Baker & Co., 
Wilmington, Del., and others. 



CHAPTER XXI. 

MACHINES FOR MEASURING LEATHER. 

THE heavy leathers are sold by weight ; but light leathers, 
such as upper, morocco, sheep-skin, and enamel leather, are 
sold by area in the United States. The yardstick, and the 
common measuring frame, having wires or cords running the 
length and across it, thus dividing the frame into square feet, 
do not require special description. 

Tanners of sole leather by a quick process are talking of 
selling sole by measure instead of weight. They claim that the 
buyer gets nothing but leather when made by this process. An 
idea being broached by shoe manufacturers is to have the frac- 
tion of a foot reduced to eighths instead of quarters, as is done 
on the measuring machines. Nearly all large manufacturers 
remeasure their leather, and discrepancies are often found be- 
tween theirs and the original measurement. 

sawyer's leather measuring machine. 

The Sawyer self-adjusting leather-measuring machine is 
shown in Fig. 92. It is sold by the Sawyer Leather Machinery 
Co., Boston, Mass. It is constructed on a different principle 
from other machines for measuring the areas of surfaces, and 
it can be operated by either hand or power. 

A minimum of power will run this machine, and it can be 
operated at a fast or slow rate of speed ; 65 revolutions per 
minute is a good average, which gives five sides in that time. 
Wax, grain, enamel, goat and sheep-skins are perfectly meas- 
ured by this machine, which is made in three different sizes (5, 
6 and 10 feet), to suit the various leathers. The machine is 
made of metal, and any of the series of wheels may be removed 
or replaced without interfering with the others. 

( 277) 



278 



THE MANUFACTURE OF LEATHER. 



Sawyer's invention consists in an arrangement of levers by 
which the travel of each measuring-wheel is caused to properly 
affect the index of the registering device. 

The article to be measured is fed into the machine between 
the wheels and roller, and the leather is smoothed out as it 
passes between them, and so records every inch in the surface. 

Fig. 92. 




sawyer's leather-measuring machine. 



Fig. 92 illustrates a perspective view of the front of the 
Sawyer machine. 

For the purpose of establishing a standard of measurement 
of leather, the trade generally signed an agreement making the 
Sawyer measuring machine the standard. This is the first and 



MACHINES FOR MEASURING LEATHER. 279 

only formal endorsement by the trade of any invention whatso- 
ever as the standard of measure for leather. 

The Sawyer leather measuring machine was given the high- 
est award, a gold medal, at the great exhibition of the Massa- 
chusetts Charitable Mechanics' Association in 1884. Again at 
the Exhibition of 1887, it was in competition with all of the 
machines known for the measuring of leather, and again it re- 
ceived an award of first class — a special diploma, affirming the 
award of the gold medal for its continued excellence, while no 
other measuring machine received an award above the fourth 
class. (For confirmation of this statement we refer to the 
records of the Mass. C. M. Association.) The reasons for this 
distinction are that the Sawyer is the only machine measuring 
accurately every description of leather in any condition whatso- 
ever, wrinkled or smooth, and is consequently the only machine 
available to manufacturers of boots and shoes whose stock 
comes to them folded and creased. It stands, therefore, alone 
in its universal application, and is now practically regarded as 
the standard of measure for all upper leather in the United 
States, England and Germany. 

THE UNION LEATHER MEASURING MACHINE. 

Fig. 93 illustrates the Union leather measuring machine, 
which is offered to all who deal in leather in any form and now 
in constant and most satisfactory use by well-known dealers. 

Experience has demonstrated that this machine has no equal 
for accuracy, rapidity, ease, and simplicity of action, and for 
low cost both of running and of original purchase. 

The machine is made in three sizes: No. 1, 5 x 4; No. 2, 
6 x 4^ ; No. 3, 10 x 4^ feet. The Union Leather Measuring 
Machine Co., Danversport, Mass., who manufacture the ma- 
chine, are willing at any time to meet all competitors in a trial 
for accurate measurement. Wm. O. Hood, Danversport, Mass., 
is the agent for the sale of the machine. 

This machine is a simple mechanical arrangement for rapidly 
measuring, within a very small limit of error, the superficial 



280 THE MANUFACTURE OF LEATHER. 

Fig. 93. 




area of any plain surface having a close texture, regardless of its 
irregularity of outline. This difficult problem is accomplished 
by means of a flat grid or table of suitable height and properly 
framed, the area of top being formed of wooden strips about 
seven-eighths of an inch thick and set at right angles to the 
front, with interstices of 1 ^ inches. Upon the table the object 
to be measured is placed. Above the table, and corresponding 
thereto in its area, is a double frame hung upon anti-friction 
pivots at the back, so as to open like a trunk cover, or close 
down to a suitably fixed distance from the table. Throughout 
the entire surface of this upper frame are suspended, at inter- 
vals of \y 2 inches by 2 inches, small wires (free to slide up 
through holes) of such sizes and lengths that each will exercise 
the same influence as to weight as any other, that is to say, the 
nearer the fulcrum the heavier the wire. The weight of forty- 
eight of these wires corresponds to one square foot of area, and 
thus the upper frame containing them being brought down to 
the table, the object thereon throws up all the wires which come 
in contact with it, and the ends of the remaining wires drop be- 



MACHINES FOR MEASURING LEATHER. 28 1 

tween the slats of the table. The released weight of the wires 
which have been thrown up is indicated by a spring balance 
down to one-eighth of a square foot. However irregular the 
the outline, the area will be embraced by the pins down to a 
section of 1 ]/ 2 by 2 inches, the error of one pin being but the 
forty-eighth of a square foot ; it thus approaches absolute accu- 
racy very closely 

THE BOLTON MACHINE. 

J. P. Bolton, Boston, Mass., has invented a planimeter for 
showing the area of leather. The leather is drawn over the 
table between a roll and a series of integrating wheels, mounted 
in pivoted and adjustable frames. Back motion is prevented 
by pawls, which can be simultaneously thrown out of action by 
an eccentric operated by a crank and handle bar when it is de- 
sired to zeroize the apparatus. The wheels have coiled in their 
hubs cords leading to weights in a series of tubes partially filled 
with liquid and connected to a tank. A tube is also connected 
to the tank and provided with a float carrying a graduated 
scale. Whenever any wheel is rotated by a portion of the skin 
passing beneath it, the corresponding weight is drawn up- 
wards. The movement of all the weights is instigated by the 
movement of the water level in the tube, and the area is read 
oft* from the scale. 



CHAPTER XXII. 

MINERAL TANNING SUBSTANCES — " CHROME," OR MINERAL 

TANNAGE — CHARACTERISTICS OF CHROME-TANNED 

LEATHER — CURRYING — DYEING. 

The use of mineral tanning materials dates back to very re- 
mote times, since history teaches us that the Saracens used 
alum and aluminium salts for tanning skins. These substances 
were in fact for a long time the only tanning materials em- 
ployed for preparing leather, a series of other mineral sub- 
stances for tanning having been only recently introduced as a 
substitute for vegetable substances. 

The principal mineral substances we have to consider are : 

1. Alum, aluminium sulphate and aluminium acetate. 

2. Chromates and chromic oxides. 

3. Hyposulphite of soda. 

4. Ferric salts. 

5. Common salt. 

ALUMINIUM SULPHATE. 

Neutral aluminium sulphate (A1 2 3S0 4 ) is prepared either by 
treating clay or bauxite with concentrated sulphuric acid, or 
from cryolite. In an anhydrous state it contains 30 per cent, 
of alumina and 70 per cent, of sulphuric acid. With eighteen 
equivalents of water it crystallizes into octahedrons or at a 
temperature of 32 F. into hexagonal rhombohedrons. Alu- 
minium sulphate is soluble in double its weight of water. A 
solution prepared with the assistance of heat separates, on 
cooling, crystalline lamina or aluminium sulphate (A1 2 3S0 4 + 
i8H 2 0). It is found in commerce in a nearly pure state, the 
best qualities containing only traces of iron, but from 0.5 to 2 
per cent, of free sulphuric acid, which is frequently injurious 

( 282 ) 



" CHROME," OR MINERAL TANNAGE. 283 

when the salt is to be used for tanning purposes. The presence 
of free sulphuric acid may be detected by adding to a so- 
lution of aluminium sulphate some logwood tincture. The 
solution, if free acid is present, will be colored brown-yellow ; 
deep violet, if it is neutral. To make aluminium sulphate con- 
taining free sulphuric acid available for tanning purposes, add 
to a solution of it 1 to 2 per cent, of zinc chips, the solution of 
which will be attended by a violent development of hydrogen. 
By the free sulphuric acid combining with the zinc, zinc sul- 
phate is formed. An excess of zinc is dissolved with formation 
of zinc sulphate and separation of basic sulphate of alumina. 
Instead of zinc chips 1 to 2 per cent, of sodium carbonate may 
be used. 

Aluminium sulphate, known in commerce as concentrated 
alum, is used in tanning as a substitute for alum. The skin 
absorbs, according to Knapp, up to 27 per cent, of it, which is 
removed by washing with water. 

Alum (A1,3S0 4 + K 2 S0 4 + 24H 2 0), is formed by the combi- 
nation of aluminium sulphate with alkaline sulphates. It is 
readily prepared by mixing solutions of the two sulphates. In 
evaporating the fluid, the alum crystallizes ont. Potash-alum 
and ammonia-alum dissolve with difficulty, they requiring 18.4 
parts of cold water and 7.5 parts of boiling water, while soda- 
alum dissolves readily. From a hot saturated solution, the 
alum separates in octahedrons, and from alkaline solutions in 
hexadrons. The last variety is called in commerce cubic alum, 
and, being nearly free from iron, is valued more highly than 
the former. Alum has at first a sweetish taste which changes 
into an astringent. By heating it loses gradually its water of 
crystallization, becomes anhydrous, and is converted into the 
so-called burned alum. Ferric sulphate, manganous sulphate, 
and chromium sulphate, which are isomorphous with alumin- 
ium, form also double salts when combined with potassium, 
sodium, or ammonium sulphate. The resulting combinations 
are called iron alum, chromium alum, and manganese alum. 
Instead of alumina they contain ferric oxide, chromic oxide or 



284 THE MANUFACTURE OF LEATHER. 

manganic oxide. They crystallize in the same form, and con- 
tain an equal quantity of water of crystallization : — 

Iron alum = Fe 2 3S0 4 + K,S0 4 + 24H 2 0. 

Manganese alum = Mn 2 3S0 4 + K 2 S0 4 + 24H 2 0. 

Chromium alum = Cr 2 3S0 4 + K 2 S0 4 -f 24H 2 0. 

If several of these alums in solution are present in one fluid, 
the crystals separating from it contain the different bases in 
varying quantity. It is due to this circumstance that alumina 
alum contains frequently iron alum, which it is often impossible 
to remove even by repeated recrystallization. In tawing and 
in mineral tanning potash-alum is principally used. 

For a complete saturation the skin tissue absorbs, according 
to Knapp, 7 to 8 per cent, of alum. 

The tanning properties of alum are principally due to the 
alumina salts it contains. 

In absorption by the skin tissue, the alum, according to 
Knapp and Raimer, is split, the aluminium sulphate or basic 
aluminium sulphate precipitating upon the fibre, while the 
potassium sulphate remains in the liquid. In the presence of 
common salt in aqueous solution, the alum, according to Knapp, 
is not converted into aluminium chloride and sodium sulphate. 

Iron and chromium alum act upon the skin tissue in the same 
manner as aluminium alum. 

Aluminium acetate (Al 2 6(OC 2 K 8 0) ) is prepared by dissolv- 
ing alumina in acetic acid or compounding lead acetate with 
aluminium sulphate or alum. Heating during the process 
should be avoided. Experiments have lately been made in 
using aluminium acetate in place of aluminium sulphate or alum. 

It does not separate, it is claimed, in a crystalline form in the 
skin, and the leather tanned with it does not become spotted, 
as is frequently the case in tanning with alum. The tanning 
with this salt is more solid than with alum, since the aluminium 
acetate decomposes more or less in the leather by the formation 
of basic salts or free alumina. 

A further advantage claimed for aluminium acetate is the 
absence of free sulphuric acid, which is split off from the 



"CHROME," OR MINERAL TANNAGE. 285 

aluminium sulphate and exerts a very injurious influence upon 
the leather. 

CHROMIUM SALTS. 

Experiments have been made to use chromates mixed with 
alumina salts for tanning in place of vegetable substances. 

The most important for this method of tanning is potas- 
sium bichromate, from which all other chromic salts and com- 
pounds of chromium used for technical purposes are derived. 
The salt is chiefly manufactured in three large eslablishments 
in England, from whence it is sent to all parts of Europe and 
partly to America. It is made by roasting a mixture of finely 
powdered chrome iron-stone with potassium carbonate upon the 
hearth of a reverberatory furnace for several hours with con- 
stant stirring of the mass. The chromium oxide is oxidized to 
chromic acid, the latter combining with the potassium to potas- 
sium chromate. The ferric oxide contained in the chrome iron- 
stone is separated as such. After thorough oxidation the 
roasted mass is lixiviated with water, whereby potassium chro- 
mate, a small excess of potassium carbonate and a few impurities, 
such as potassium silicate, pass into solution. The liquid 
is allowed to clarify by standing, and, after decanting, is evapo- 
rated if necessary, and the neutral potassium chromate con- 
verted into potassium bichromate by adding the required 
quantity of sulphuric acid. The potassium bichromate forms 
large bright garnet-red triclinic crystals.- It is soluble with 
difficulty in cold water. 

20 parts of water at 32 F. dissolve 1 part of salt. 

11.8 " " " 50 " " 1 " " 
7.65 " " " 68 " " 1 " " 
1. 18 " " " 140 " " 1 " " 

Potassium bichromate is very sensitive. With glue, gelatine, 
gum, etc., it forms combinations which, after exposure to light, 
are insoluble in water, its employment in photography for 
preparing pigment or carbon pictures depending upon this 
property. Advantage is taken of this fact in several patents 
for chrome tannage. 



286 THE MANUFACTURE OF LEATHER. 

It precipitates itself upon the skin fibre, and partially pene- 
trates it. 

Taken internally it has a poisonous effect like most metallic 
combinations. Placed repeatedly upon excoriated or sore places 
it produces running ulcers, which are, however, soon healed by 
washing with lead vinegar. It colors the sound cuticle yellow 
without destroying it. In pulverizing potassium chromate care 
must be had not to allow the powder to enter the nostrils, as it 
produces violent itching and severe spells of sneezing. 

Sodium bichromate is more soluble in cold water than potas- 
sium bichromate, but it crystallizes with difficulty. It is used 
in the two bath chrome processes ; but potassium bichromate 
is more generally employed. 

Calcium bichromate, strontium, and barium are soluble in 
water, while the neutral chromates of calcium, strontium, and 
barium are soluble with difficulty, the barium salt, which forms 
a well-known art color, being almost insoluble in water. Lead 
salts give with chromic salts insoluble precipitates, which are 
used as painter's colors. 

The neutral chromates are yellow, readily soluble in water, 
and can be used in place of the bichromates, but being dearer 
than the latter offer no advantage. 

Chromium alum is the most important of the chromium salts 
thus far introduced in tanning. It is prepared by mixing chro- 
mium sulphate with alkaline sulphates. It crystallizes from the 
fluid in octahedrons. 

In speaking of alum, it has been mentioned that chromium 
alum acts upon the fibre in the same manner as aluminium 
alum, but the tanning of leather prepared with aluminium alum 
being, as we will see later on, more perishable on exposure to 
water than that of leather prepared with chromates, the latter 
are preferred. 

Chromic sulphate (Cr 2 3S0 4 ) is obtained by reducing chromic 
acid to chromic oxide, and dissolving in sulphuric acid. It is 
soluble in water, giving to the latter an emerald-green color, 
and has the same tanning effect upon the skin fibre as alu- 
minium sulphate. 



"CHROME," OR MINERAL TANNAGE. 287 

HYPOSULPHITE OF SODA. 

Hyposulphite of soda is one of the materials called for by the 
two bath chrome tannage processes. This article is prepared 
as a by-product in several of the large European chemical 
factories. Attempts have been made to make it in this coun- 
try, but unsuccessfully heretofore, inasmuch as it has been 
attempted as a main product, whereas the foreign manufac- 
turers enjoy the advantage of its being a by-product. Of late, 
however, there has been successfully produced an American 
product which is proving to be merchantable. The increasing 
demand for a purer and dryer hyposulphite of soda has induced 
a company to start a large plant for producing the same. A 
very fine quality of this salt has been made in this country for 
the past four or five years, in a limited way. The same chem- 
ist that had charge of the smaller plant will be in charge of the 
larger one, and it is claimed that they can now furnish it in any 
desired quantity and of guaranteed quality. The advantages of 
the American hyposulphite of soda are that it contains less 
moisture and tests higher than the imported. A careful 
analysis of several different lots of German and English show 
that the American contains from 8 to 10 per cent, more pure 
hyposulphite than the German, and from 11 to 15 percent, 
more than the English make. 

The muriatic acid and sulphuric acid employed in the two 
bath processes are so well known that no especial description 
is necessary here. 

FERRIC SALTS. 

Tanning with ferric salts was already recommended in the 
last century by D'Arcet. Bordier, in 1842, obtained a patent 
for tanning by means of ferric sulphate produced by oxidizing 
ferrous sulphate. 

In modern times Knapp has attempted to reintroduce in 
practice the method of tanning with ferric salts. The ferric 
sulphate used by him is also prepared by oxidizing ferrous sul- 
phate with nitric acid, the latter being added to a solution of 



2 88 THE MANUFACTURE OF LEATHER. 

the former until effervescence ceases, and all the ferrous. oxide 
is converted into ferric oxide. After the cessation of the first 
effervescence ferrous sulphate is again added until effervescence 
ceases, the object of this addition being to reduce any excess of 
nitric acid used. The resulting basic ferric sulphate solution 
should be of a syrupy consistency, and contain chiefly basic 
ferric sulphate and a small excess of ferrous sulphate. 

Prof. Knapp says that only basic ferric sulphate prepared in 
the above manner is adapted for tanning, on account of its 
amorphous condition and beautiful brown-yellow color and the 
indecomposableness of its aqueous solution in boiling, The 
commercial basic ferric sulphate, according to Knapp, does not 
give a syrupy solution, is of a much darker color, and the aque- 
ous solution is decomposed by boiling. 

This ferric salt is, according to Knapp, abundantly absorbed 
by the skin tissue and effects a complete tanning of the skin 
fibre. It is claimed that the salt absorbed by the skin cannot 
be removed by treating with water. 

By precipitating a soap solution with the above basic ferric 
sulphate, Prof. Knapp prepares an iron soap, which is a combi- 
nation of ferric oxide with sebacic acids. This, to complete the 
tanning process, is mechanically fulled into the skin, either by 
itself or mixed with fat solutions or emulsions. 

COMMON SALT 

occupies an important place in tanning. It serves, as has-been 
previously mentioned, on the one hand for preserving skins, 
and on the other to accelerate the tanning process in tawing 
and mineral tanning. As regards its occurrence, preparation, 
etc., nothing need be said. 

The salt found in commerce is either rock salt or that ob- 
tained from salt springs or sea-water, the latter being known as 
common salt. Both varieties contain varying quantities of ad- 
mixtures, the principal being the sulphates of magnesia, lime, 
or gypsum, and the chlorides of calcium and magnesium. 
Common salt prepared from sea-water contains the most im- 



" CHROME," OR MINERAL TANNAGE. 289 

purities, the principal being magnesium chloride, magnesium 
sulphate, calcium chloride, etc. The salt obtained from rock 
salt by recrystallization being the purest, is especially adapted 
for use in tanning. 

In using common salt in tawing and mineral tanning, admix- 
tures of magnesium chloride and calcium chloride are espec- 
ially injurious, as they absorb water from the air, i. e., they are 
hygroscopic. 

When salt containing these admixtures is used for tanning, 
the leather produced with it absorbs water from the air and 
becomes moist. 

"chrome" or mineral tannage. 

Investigators in the field of chemistry and experimenters in 
the art of leather manufacture have sought for a long time for 
some mineral substance that could take the place of tannin in 
converting hides and skins into leather. It may be said that 
Cavalin, Knapp, Pfanhauser and Heinzerling were among those 
whose valuable investigations opened the way for future success. 

The first use of bichromates for tanning was made by Cavalin. 
The skins, according to his method, are placed in a solution of 
22 pounds of potassium bichromate and 44 pounds of alum in 
396 pounds of water, where they remain for four or five days 
with frequent stirring, when they are placed in a solution of 2.2 
pounds of ferrous sulphate in 22 pounds of water. In this they 
remain for twelve hours, being in the meanwhile frequently 
stirred. The potassium bichromate is reduced to chromic oxide 
by the ferrous sulphate, and the ferrous oxide contained in the 
ferrous sulphate oxidized to ferric oxide, both oxides being 
precipitated as such upon the fibre, or the ferric oxide together 
with alumina. The fixing of the chromium combination is 
effected by reducing the soluble chromate to chromic oxide. 
Cavalin's method may be considered as a combination of tan- 
ning with ferric aluminium and chromic oxides. But a practical 
application of the process is not possible, since the leather loses 
its tannin easily when immersed in water, and its grain is brittle. 
T 9 



290 THE MANUFACTURE OF LEATHER. 

Knapp, in 1861, obtained a patent in Germany for tanning 
with ferric salts and other metallic oxides. Hides tanned with 
mineral substances lost, like those tanned with alum, their tannin 
by immersion in water. Knapp tried to remove this evil by 
converting the metallic salts adhering externally to the skin into 
insoluble metallic soaps, by soaking and kneading the skin in a 
soap solution. In order to fix the tanning substance in the skin, 
Knapp recommended, instead of immersing the tanned skins in 
soap solution, the fulling in of insoluble soaps of ferric oxide, 
aluminium oxide, or chromium oxide. The solution of basic 
ferric sulphate Knapp used for tanning was prepared by com- 
pounding the solution with caustic soda until the resulting pre- 
cipitate was again dissolved in the fluid. 

Next to Knapp, Pfanhauser obtained in 1864 a patent for the 
preparation of a basic ferric sulphate and its use for tanning. 
By his process ferric sulphate is heated to a red heat with con- 
stant stirring until the mass is converted into a reddish powder. 
The latter while hot is thrown into water, in which, with con- 
stant stirring, it is almost entirely dissolved. The resulting fluid 
is allowed to clarify by standing, and the clear liquor used for 
preparing tanning fluid of varying strength. The skins are first 
placed in a dilute solution of O.5 Beaume, and then succes- 
sively in stronger solution. When thoroughly permeated they 
are washed off and placed in a soap solution. 

Knapp, in 1877, gave a fresh impetus to mineral tanning by 
patenting in Germany and other countries a new method of 
tanning with ferric salts, a short description of which process is 
here given : 

In the use of the basic sulphate of iron as a tanning material, 
the hides or skins, having the hair and adherent fleshy portions 
removed in the usual manner, are placed in the cold solution of 
the ferric oxide salt of the proper density, in which they are 
allowed to remain for two, or, at most, four days, during which 
time it is not necessary to handle the hides in any manner, all 
the laborious operations attending the use of tan-bark liquor, 
while the hides or skins are subjected to the action of such 



"CHROME." OR MINERAL TANNAGE. 291 

liquor, being obviated. At the end of the time named the hides 
or skins are removed from the solution of ferric-oxide salt. 
This salt is prepared as follows : To a boiling solution of sul- 
phate of protoxide of iron (green vitriol) is added as much nitric 
acid as will thoroughly oxidize the salt contained in said solu- 
tion. When the effervesence which ensues upon the addition 
of the nitric acid has subsided, the operation is reversed — that 
is, sulphate of protoxide of iron is added to the solution till said 
solution assumes a syrupy consistence — a distinguishing char- 
acteristic aforementioned — and acquires a yellow-red color, also 
characteristic of solutions of this iron oxysalt, which, when 
slowly evaporated to dryness, has the appearance of an orange- 
red transparent varnish, also highly characteristic. 

In this condition, it is claimed, the ferric sulphate possesses 
qualities differing essentially from those attributed to it in 
chemical text-books, or found in the commercial article. The 
latter gives no syrupy solution, is of a yellow-brown color, and 
in aqueous solution is decomposed by boiling, while the prep- 
aration produced according to the above method remains un- 
decomposed by boiling even in a solution of 20 to 40 B. It 
is further claimed that the ferric sulphate prepared according 
to Knapp's method is more abundantly absorbed by the skin. 

After tanning, the skins are treated with fat solutions and a 
so called iron soap. Greasing the skins by hand, hanging them 
up in the drying-room and scraping off the excess of fat is done 
away with. Stearin and paraffin are suitable materials for the 
fat solution. 

The iron soap is separated in an insoluble form by precipi- 
tating soap solution with Knapp's ferric salt. The iron soap pre- 
pared in this manner is mechanically fulled into the skin, a fulling 
drum constructed by Knapp being used for the purpose. 

A paste of iron soap is applied to the skin with or without 
an addition of fatty emulsions, or placed together with the skins 
in the fulling drum and mechanically fulled in. The skins are 
dried at the same time by the current of air passing through the 
fulling drum. The new and peculiar features claimed for this 
purpose by Knapp are as follows : 



292 THE MANUFACTURE OF LEATHER. 

1. The preparation of the ferric salt, especially the treatment 

of the ferrous sulphate oxidized by nitric acid by a 
further addition of the same salt. 

2. The treatment of the skins and hides with solutions of iron 

and fat. 

3. The use of stearin for the above purpose. 

4. The fulling drum connected with a fan by which a current 

of air is forced into it. 

5. The iron soap and its use. 

The advantages of this method of tanning are, according to 
Knapp — 

1. Greater cheapness (from 5to25 percent.). 

2. Considerable saving of time, the product being of an equal 

quality and durability. 

3. The obtaining of as large a yield as by tanning in the ordi- 

nary manner. 

4. The use of a tanning material of a constant chemical com- 

position, by which the obtaining of a uniform product is 
assured. 

The leather prepared by Knapp' s process had a brown-yellow 
color closely resembling that of leather tanned by the ordinary 
manner. It is, according to Knapp, not water-proof but capa- 
ble of resisting water, meaning by this that the leather does not 
lose its tannin by frequent contact with water. As far as we 
know, this process was only used for the preparation of sole and 
belt leather, and we are unable to say whether upper leather 
was later successfully produced. 

We will say nothing further pro et contra in regard to this 
method. 

Knapp also applied for an additional patent for a somewhat 
different method of preparing the ferric salts. Instead of add- 
ing, as formerly described, nitric acid to a boiling solution of 
ferrous sulphate, an equivalent quantity of sulphuric acid and 
sodium nitrate is added to the ferrous sulphate solution. The 
tanning with this is effected in the same manner as previously 
described, but can also be done by the precipitate which albu- 



" CHROME," OR MINERAL TANNAGE. 293 

minous substances, as for instance that of blood, produce with 
the ferric solution. 

In the years 1880 and 1881, Heinzerling obtained patents in 
the United States, and previously in other countries, for quick 
tanning with chromates, with an addition of aluminium salts, 
sodium chloride, etc. 

The process is executed as follows : 

The skins are cleansed, depilated, and swelled, and placed in 
a one-quarter per cent, solution of chromic acid or in a half per 
cent, solution of potassium bichromate, sodium bichromate, or 
magnesium bichromate or other neutral bichromates, or in a 
half per cent, solution of chromic salts, for instance chromic 
sulphate. It is advantageous to add to the solution one per 
cent, of alum or aluminium sulphate or other aluminium salts, 
and one per cent, of sodium chloride. According to their thick- 
ness the skins remain in the solution a shorter or longer time ; 
calf-skins, for instance, four to six days, and heavy bullock 
hides up to fourteen days. During this time the solution is 
successively concentrated until it contains as much as 6y£ per 
cent, of chromates, 12 per cent, of alum, and 10 per cent, of 
common salt. 

The action of tanning liquors gradually increasing in strength 
can also be effected in a more simple manner by placing the 
skins successively in more concentrated solutions and allowing 
them to remain a corresponding time in each of the solutions. 

When fresh skins are placed in the tanning-liquors, the tan- 
ning substance withdrawn by the skins taken out must be 
always supplemented, the quantity required being determined 
by analysis. 

Although experience has shown that the tanning process can 
be executed without the use of aluminium combinations and of 
common salt, it is advantageous to employ them, since these 
substances possess also tanning properties and accelerate the 
process, and besides being comparatively cheap, reduce the cost 
of the operation. 

If leather is to be produced which is to be blackened after 



294 THE MANUFACTURE OF LEATHER. 

tunning, 2 to 3 per cent, of potassium ferric-cyanide or potas- 
sium ferro-cyanide is added to the solution. These substances, 
together with the iron black applied later on, give a deep dark- 
blue color to the leather. 

After tanning in the described solutions, the skins are placed 
in a 4 to 8 per cent, solution of barium chloride, acetate of lead, 
or soap, which effects a partial fixing of the tanning substance 
by the latter forming with the first insoluble salts or soaps. 

To effect a quicker absorption of the barium chloride, ace- 
tate of lead, or soap, the skins, while in the solutions, are vigor- 
ously moved or kneaded. They are next washed, superficially 
dried and stretched, and, while still feeling somewhat moist, 
placed for 36 hours in a solution of stearin, paraffin, wax, rosin, 
colophony, spermaceti, or of other hydrocarbons or fat, in 
benzine or other solvents having a similar effect. 

It is advantageous to heat the solution containing fat, paraffin 
or other hydrocarbons to 96. 8° F. in a water-bath. In place 
of stearin or the other substances mentioned, a mass resembling 
caoutchouc can be used, which is obtained by treating oils 
(linseed or rape-seed oil) with 10 to 15 per cent, of chloride of 
sulphur. If chromic acid is used in tanning, the paraffin em- 
ployed in the after-treatment is oxidized by the acid, the latter 
being at the same time reduced to chromic oxide. The paraf- 
fin appears to become oxidized to an acid-like combination 
which enters with the chromic oxide, formed into a combination 
insoluble in water, which is firmly precipitated upon the fibre. 
When chromates are used, the chromic acid is split off from the 
chromates during the tanning process, either by the skin itself, 
or, in case aluminium salts are employed, by the sulphuric acid 
liberated from them. By the succeeding treatment with paraf- 
fin, etc., the insoluble combination described above is also 
formed. As a proof of the described action taking place upon 
the paraffin, we would mention the fact that the cut surface of 
leather prepared according to the described process is at first 
yellow, but becomes gradually lighter, especially when exposed 
to the light, and turns finally to a nearly whitish-green. Metallic 



" CHROME," OR MINERAL TANNAGE. 295 

salts, for instance cupric sulphate and others, can be added to 
the solution of chromates formerly mentioned, partly on ac- 
count of the tanning effect of these salts, and partly in order to 
produce certain shades of color upon the leather. 

The skins can also be placed, either before or after they have 
been treated with the described tannin liquors, in solutions con- 
taining vegetable tannin. 

After the skins have been removed from the solutions of fat, 
paraffin or rosin, the leather intended for uppers and belts is 
greased in the same manner as leather tanned in the usual 
manner, with a mixture of tallow, train oil, or similar fat mix- 
tures. After greasing, the fat is either fulled in or allowed to 
soak in by hanging the skins in a moderately heated room. 

The upper leather is, generally speaking, curried in the same 
manner as leather tanned by the ordinary process, a few points 
only requiring special precautions to assure a fine product. 

In preparing black grain leather, it is best to blacken the 
skins before placing them in the fat solutions. For blacking, 
on account of the yellow ground being more difficult to 
blacken, the application must be repeated once or twice oftener 
than for leather tanned in the ordinary manner. 

If the leather is to be blackened after greasing and currying, 
the fat must first of all be thoroughly removed by scouring 
with dilute solution of soda or ammonia, and rubbing with 
pumice stone powder, or wood ashes. The grain side thus 
cleansed is then blackened with logwood extract or iron black. 

Sole leather tanned by the above process is, after removal 
from the tanning liquor, impregnated with solutions of fat, wax, 
or rosin. It is then dried or rolled. 

In working the upper and sole leather into shoes, the follow- 
ing directions should be observed : In order to be able to last 
the upper well, it should be placed in luke-warm soap-liquor 
for 10 to 12 hours and frequently kneaded. Lasting can only 
be accomplished in the ordinary manner after the fluid has 
thoroughly permeated the grain, which is more difficult to effect 
than with leather tanned in the usual manner. Chromium leather 



296 THE MANUFACTURE OF LEATHER. 

it is claimed is more water-proof. The property of the leather 
of not stretching after having been worked, deserves special 
attention, since a shoe made a close fit, as is generally the case 
with leather tanned in the usual manner, is apt to be too tight. 

For sole leather to be easily worked it is not sufficient to dip 
it simply in cold water; it should remain for some time in luke- 
warm water. 

Experiments which have been made in regard to the absorp- 
tion of water by leather tanned in the usual manner and that 
prepared with chromates, have shown that the latter absorbs 
water slower and a smaller quantity of it than the former. 

A further advantage of chrome leather is that it possesses the 
property of losing less tannin by repeated treatment with cold 
or warm water than leather tanned in the usual manner. 

The use of iron alum and chrome alum was at one time pro- 
posed and actually introduced into practice. But the use of 
these substances was soon abandoned, as the leather prepared 
in this manner had no advantage over that tanned with alum 
and alumina salts. 

All the above-mentioned methods of tanning have been aban- 
doned on account of the defective quality of the product pro- 
duced by them. But this can scarcely be attributed to the 
properties of the tanning material, but rather to the errors com- 
mitted in their preparation. By immersing leather prepared 
with these tanning materials in tan-liquor it was made closely 
to resemble that tanned in the ordinary manner. 

While the experiments of Cavalin, Knapp, Pfanhauser and 
Heinzerling led to no immediate practical results, they were, 
nevertheless, of immense value, as laying the foundation for 
others, who came after them, to build upon. In seeking for 
this mineral tanning substance it was necessary that the new 
material should possess certain characteristics which would in- 
duce tanners to use it; namely, it should be obtainable in great 
abundance ; it must be as cheap or cheaper than tannin ; it 
should be quicker in its action, so that time might be saved ; 
it should be as simple, safe and easy in its application as a de- 



"CHROME," OR MINERAL TANNAGE. 297 

coction of tannin ; it should produce a leather superior to that 
made by the older methods. 

The salts of aluminium, iron and chromium, either, alone or 
in various combinations, were found to be useful in converting 
raw hides into leather, but the great majority of the processes 
covering the use of these metallic salts for tanning were found 
to be utterly impracticable, because lacking in one or mere of 
the above-named essential characteristics. It remained, how- 
ever, for American ingenuity to solve the problem. Through 
processes invented by Americans, all other metallic salts have 
been eliminated and the application of the salts of chromium 
has been made to fulfill all requirements. The two methods 
of chrome tanning now in practical use, and by which all 
chrome leather is made both in Europe and America, may be 
designated as the "two bath" process, patented by Augustus 
Schultz, and the "one bath" process, patented by Martin Den- 
nis. The Schultz patents are owned by the Tannage Patent 
Company, of Philadelphia, Pa., who issue licenses to tanners and 
charge royalties for the use of the process. The Dennis patents 
are owned by the Martin Dennis Chrome Tannage Company, 
of Newark, N. J., who manufacture the chrome tannage material 
under the trade-mark of "Tanolin" and sell the material out- 
right to tanners without licenses or royalties. 

A detailed description of these two methods of chrome tan- 
ning is given in another part of this volume. In this connec- 
tion, however, a description, in general terms, of the Schultz 
process and the Dennis process and a statement of what has 
been accomplished in the way of chrome tanning by these two 
methods will be of interest. 

In the Schultz method, the skins, after being fully prepared 
for tanning, are immersed in a bath containing a solution of 
bichromate of potash and muriatic acid. This is called the 
" first bath," in which the skins remain until they have absorbed 
sufficient of the chromic acid. The skins are then placed in 
the " second bath," which is a solution of hyposulphite of 
soda, to which muriatic acid is added. The chemical reaction 



298 THE MANUFACTURE OF LEATHER. 

in the "second bath" sets free sulphurous acid, which acts as 
a reducing agent upon the chromic acid in the skin, forming 
chromic oxide, which unites with the fiber of the skin convert- 
ing it into leather. The proportions of bichromate of potash 
and acid in the "first bath" and of hyposulphite of soda and 
acid in the "second bath" have to be very carefully adjusted 
to a given amount of raw hide substance, which is determined 
by weight. To learn these proportions, as applied to different 
kinds of hides and skins, requires considerable experience ob- 
tained through practice. When Mr. Schultz first endeavored 
to draw the attention of tanners to his process it was severely 
criticised and was considered on all sides to be a difficult, com- 
plicated and dangerous process of tanning. It was not until 
Mr. Robert H. Foederer, of Philadelphia, and Mr. Wm. Zahn, 
of Newark, N. J., made commercial leather which was consid- 
ered superior to any heretofore produced, that any serious con- 
sideration was given to the Schultz process. At the present 
time the process is largely used in the production of glazed kid 
and for certain classes of glove leather ; in fact the American 
chrome-tanned glazed kid is conceded to be the most beautiful 
fabric ever produced for use in the making of ladies' shoes. 
Not only do the American shoe manufacturers use the chrome- 
tanned glazed kid almost exclusively, but large and increasing 
quantities of this leather are being exported to European 
countries. 

By the Dennis " one bath " process the art of chrome tan- 
ning has been greatly simplified. A dilute solution of a basic 
or oxy-salt of chromium is used in which the chromic oxide is 
held so loosely that it readily yields this oxide to the skins 
placed in the solution. In fact the skins absorb the chromic 
oxide from the solution in the same manner as the skins would 
absorb tannin from a bark liquor. In the Dennis process the 
skins are not subjected to a drastic chemical reaction, nor are 
they exposed to the action of corrosive acids, which in other 
processes often produces irreparable damage to the resulting 
leather. Tanolin is the name given to the Dennis one-bath 



" CHROME," OR MINERAL TANNAGE. 299 

chrome tan liquor, and it is designed to afford leather manu- 
facturers an easy, cheap and reliable method of producing 
chrome leather. It is offered to tanners in a compact, con- 
venient and concentrated form, all ready for use. Tanolin has 
no smell and will not even stain the hands ; it is handled in a 
simple, straightforward manner, in much the same way as a 
bark, gambier or sumac liquor. Any tanner of ordinary ex- 
perience can handle tanolin with confidence and safety. No 
change or special fitting up is required in a tannery in order to 
use it, and the usual apparatus and appurtenances found in a 
well-appointed tannery are all that is required for the success- 
ful use of tanolin. 

The advantages obtained by the use of tanolin must be ob- 
vious to any unprejudiced tanner, but they are enumerated 
below to give emphasis to the point; 

First. The tanning is accomplished in one bath. 

Second. The tan-liquor is clean, without stain or smell, and 
can be handled by workmen without risk. 

Third. The tanning material is all prepared for use, and does 
not require an expert to prepare the tanning bath. 

Fourth. The tanner can handle the chrome liquor as he has 
been accustomed to handle sumac or gambier liquor. 

Fifth. The tan liquor can be modified in its application so as 
to tan slowly or quickly as it is desired. 

Sixth. It can be used successfully in paddle wheels, revolv- 
ing drums, or in vats with rockers. 

Seventh. The tan liquor does not lose strength, change char- 
acter or turn sour on exposure, and can be kept indefinitely. 

Eighth. The old liquors can be used and exhausted, so that 
great economy can be attained in the cost of tanning. 

Ninth. The chrome leather is produced without the risk at- 
tending the use of corrosive materials and acids as in other 
processes, and, therefore, the results obtained are more uniform 
and reliable. 

Upon these and many other considerations it is claimed for 
the Dennis "one-bath" process that it is the easiest, safest, 



300 THE MANUFACTURE OF LEATHER. 

cheapest and most reliable system of chrome tannage yet 
devised. 

The Dennis process, without doubt, offers to tanners a most 
inviting field for exploitation, and one can hardly realize what 
changes may be wrought in the future by this method of 
chrome tanning. It is surprising what has already been accom- 
plished with it in its application to the production of various 
kinds of leather. The author would mention that he has seen 
the following varieties of leather tanned by this process, and all 
of them of the very finest quality : Machine belting, made by 
Geo. F. Troutwine & Co., Gloversville, N. Y. ; harness leather, 
made by The J. G. Hurkhamp Co., Fredericksburg, Va. ; hard 
sole leather, made by D. M. Easton, East Weymouth, Mass. ; 
upper leather, made by Hayes & Co., Belvidere, N. Y. ; glove 
leather, made by Brower & Dodge, Gloversville, N. J. ; glazed 
kid, in blacks and colored, made by Lennox & Briggs, Haver- 
hill, Mass. ; chamois leather, from fleshers, made by the Enter- 
prise Chamois Works, Philadelphia, Pa. ; picker band leather, 
made by Prakke Bros., Eibergen, Holland ; patent and enamel 
leather, made by S. Halsey & Son, Newark, N. J. The Dennis 
process is simple, cheap, quick and reliable. In this day of 
enterprise and activity tanners are forced to leave old ruts and 
to keep thoroughly posted on every new process and improve- 
ment likely to prove of advantage and profit to them. 

The modern tanner cannot stand still — the whole world 
teaches us that. Electricity is driving out steam power, com- 
pressed air is likely to drive out electricity as a power, and 
aerial navigation is no longer a dream, but a reality. To stand 
still is to be passed by more enterprising men and completely 
distanced in the commercial race. 

Of course tanners in embarking in the new field of chrome 
tannage will have to have their wits about them. 

Men who are not practical in the business, such as curriers 
of bark leathers, should be replaced by men specially compe- 
tent for every department. A superintendent, thoroughly prac- 
tical in every detail, should be untrammeled in his operations. 



"CHROME," OR MINERAL TANNAGE. 301 

With competent men in charge, there is no reason why fancy- 
colored chrome, glazed calf and imitation kangaroo should not 
be turned out with entire success American morocco and kid 
manufacturers are at the top of the ladder, and manufacturers 
of chrome and combination calf and sides should adopt their 
methods. They are worthy of emulation. 

Foreign methods of working, that is, foreign to the business, 
have been chiefly responsible for failure in getting out mer- 
chantable kids. For instance, take the question of shaving and 
putting out skins. It is a mistake to stick to the old currier 
style of shaving on the wooden beam-face. It has been turned 
down by the regular men in the business a century ago. Its 
defects are not so noticeable in dull or kangaroo finish as in 
glazed black or fancy colors. It is utterly impossible for a 
shaver to do good work on a wooden beam, from the fact that 
it cannot be kept in proper working order. So long as there is 
any hand shaving to do, the glass beam-face is the proper one 
to use. 

Skins should be put out on a morocco table and by a regu- 
lar morocco dresser. It is very important to put out fancy 
colors, chrome, calf and imitation kangaroo from calf and kip, 
tight. 

Chrome tannage is increasing rapidly in use and favor. 
There is an attraction in this method of making leather that is 
almost fascinating. Many leading tanners have been using 
chrome tannage for a long time, but during the past year tan- 
ners all over the country have been quietly experimenting with 
chrome liquors on upper and sole leathers. 

Chrome upper, both in black and colors, is remarkably tough 
and pliable. It is astonishing how strong and supple even light 
skins may be made by chrome liquors. Chrome tannage makes 
leather comparatively fireproof, which is a feature of much 
value. During wet or cold weather people are in the habit, on 
returning indoors, of pushing their shoes near heat or fire. 
Bark-tanned leathers are very sensitive to heat, and liable to 
burn readily. Shoe manufacturers and wholesalers are fre- 



302 THE MANUFACTURE OF LEATHER. 

quently troubled by shoes returned with burnt uppers. Those 
who bought and wore such shoes, thoughtlessly placed them 
near the fire, and then found the leather damaged. Without 
referring to the application of heat, they boldly accused the 
storekeeper of selling them inferior shoes, and worried him into 
replacing them with a new pair. The storekeeper in turn 
passes the burnt shoes to the firm from whom he bought them, 
demanding recompense or duplication. 

Chrome-tanned leathers may be boiled for several minutes 
with impunity, or exposed to strong heat for some time without 
injury. The process is not specially new, but has been much 
improved. Pioneers made and lost fortunes in it. To-day, 
however, chrome tannage is much better understood, and in- 
structions and material are obtainable by which those previ- 
ously ignorant of it may be guided with safety to success. 

Although chrome tannage has thus far been applied chiefly 
to goatskins, it is becoming considerably used on kip, calf, and 
even side-leathers. It is beginning to compete with bark. Bark 
tanners are encouraged to experiment with chrome, foreseeing 
many advantages in the saving of labor, etc. Chrome tannage 
takes shorter time and does away with bark piling, cost of in- 
surance, interest, etc., on bark stacks, grinding, leaching, and 
the labor and expense connected with leach houses. 

Those who are tanning sole leather by the chrome process 
have every reason to be gratified at results. The pretty leather 
seems to be ideal material for the bottoms of shoes for cycling, 
athletics, etc., being light in weight, delicate green or greenish- 
blue color, very tough and pliable. Chrome leather is also 
excellent for slippers, Goodyear insoles, for soft shoes required 
by old people, and invaluable in hospitals, etc., where noiseless 
tread is necessary. 

While tanners are paying close attention to chrome, their 
demands are being met by concerns that either furnish the 
instruction, or supply the chrome liquors ready for use. 

The popularity of cycling, golf and other outdoor sports has 
given marked impetus to the demand for what are known as 



" CHROME," OR MINERAL TANNAGE. 303 

sporting shoes. Shrewd shoe manufacturers, foreseeing the 
broadening field of athletics, have prospered by studying the 
requirements and supplying the wants of this field rather than 
sticking to the old and familiar staple lines. Those who are 
manufacturing sporting shoes seem quite satisfied not only with 
what they have done so far, but with the outlook for the future. 
All who take pleasure in outdoor sports and recreation are 
willing to pay a fair price for the necessary boots and shoes, 
and are not very particular as to the shape or trimmings. The 
pedestrian or runner avoids " razor toes." Such men favor 
common-sense lasts, and do not ask for changes in style, but 
rather that their shoes be strong, durable and comfortable. 

The growing enjoyment of outdoor exercise is proved by the 
fact that many leading hardware houses have established de- 
partments for the sale of sporting goods, including shoes. 
Their customers, particularly those from the country, like to 
get these supplies at one place, and the enterprising merchants 
strive to accommodate them. For a long time hardware and 
seed stores have carried cut soles, many of them disposing of 
quite a quantity of leather in this manner each year. 

Manufacturers of boots and shoes for sportsmen and athletes 
are fortunate in having to confine their solicitations either to the 
better class of retail stores or other desirable distributors. The 
smaller shoe dealers do not expect any of this kind of business. 

It cannot be denied that much of the pleasure on land or 
water may be made or marred to a considerable extent by 
one's boots and shoes. Consequently, while there may be 
economies in clothing, active, healthy men and women do not 
grudge what might be called liberal expenditure in covering 
their feet. The ever-ready and alert shoe manufacturer who 
has studied the art of making the right kind of shoes for cyclers, 
athletes, hunters, fishermen, etc., is finding his reward to-day. 
And his trade will grow according to the comfort, quality and 
judicious advertising of his product. 

Some of the leading sole-leather tanners, noting the new 
trend of trade, are studying to increase the supply of chrome 




U- 



304 THE MANUFACTURE OF LEATHER. 

tanned sole, as it is apparent that this leather is excellently 
adapted for the peculiar toughness and pliability needed in 
shoes for cycling and other purposes. 

There is an increasing demand for bicycle, golf, athletic and 
sporting shoes. The manufacturers are beginning to pay at- 
tention to this new feature of their trade, and the result is that 
there are several styles of such shoes now on market. 

In his advertisement a prominent New York dealer says : 
"My lines of bicycle shoes are designed with the utmost 
care for comfort and style, and every important point is con- 
sidered as carefully as in the manufacture of the highest grade 
wheel." 

This seemed to us putting it rather strong, and, in a recent 
conversation, the advertising manager of the house said to the 
writer : " The advertisement states the truth, for we do consider 
every point about the shoe with all possible care. We are 
trying to make a reputation for our bicycle shoes. We want 
the trade of bicyclists, both men and women, and, if we can 
become known as the makers of the best bicycle shoe, it 
should result in a growing and profitable business. The time 
to make that reputation is at the start and before other makers 
take the lead." 

Bicycle, golf, athletic and sporting shoes should be soft, 
strong, fine and durable ; they should be easy on the feet and 
handsome in appearance. The sole leather for these shoes 
should be made from steer hides, and the shoes should be 
tough, elastic, and noiseless. Chrome tannage seems to be the 
only way known of treating the hides so that these desirable 
results can be produced.. 

TANNING CALF OR GOATSKINS BY THE CHROME PROCESS. 

The Martin Dennis Chrome Tannage Co. publish these di- 
rections for using tanolin on calf or goatskins. This is the 
" one-bath" process : 

I. On removing the skins from the bran drench it is well to 
mill them in a drum in a pretty strong solution of alum and salt. 



" CHROME," OR MINERAL TANNAGE. 305 

The use of the alum and salt, however, is optional. The object 
in using the alum and salt is to keep the skin open and plump, to 
prevent them from drawing on the grain and to keep the skins 
during the process of tanning in such condition that they 
can be worked and set out with a slicker after being tanned, 
without having that spring to the leather which a good many 
complain of in working and currying chrome leather. 

2. Take the skins from the alum and salt solution, and place 
them in a bath containing a 3 per cent, solution of tanolin, to 
which a liberal quantity of common salt is also added. 

3. As the skins absorb the tanolin, the tanning liquor will be- 
come lighter in color. To strengthen the liquor add more of 
the concentrated tanolin to the tanning bath, a quart or a gal- 
lon as the case may be, but always enough to maintain the 
color of a 3 to 4 per cent, solution. It is advantageous from time 
to time to correct the tanolin liquor by adding to it slowly and 
carefully a solution of sal soda prepared in the proportion of I 
pound of sal soda to 3 gallons of water. This soda solution 
may be added until the tan liquor begins to appear cloudy ; 
then stop. This procedure will render the tan liquor so sensi- 
tive that it will yield to the skins the whole of the tanning ma- 
terial. By correcting the liquors as above indicated, the old 
liquors may be made over and over again by simply adding 
more tanolin with each new pack, so as to maintain the color 
of a 3 to 4 per cent, solution. When the skins have assumed 
a uniform greenish blue color, and by wringing the neck of a 
thick skin it wrings out dry, and by cutting a section of the 
part wrung out the skin appears fibrous throughout, the skins 
are tanned. 

4. On removing the skins from the tanning bath, they should 
be rinsed off in clean water to remove the adhering liquor ; 
not washed for any length of time, but simply rinsed off. The 
skins should then be struck out on the flesh side with a slicker ; 
the tables used for this purpose should be perfectly clean and 
free from any grease or oil, so that the grain may be protected 
from any extraneous substances, for in this condition the grain 

20 



306 THE MANUFACTURE OF LEATHER. 

of the skins will absorb stain or grease easily and quickly, and 
interfere afterwards wirh the coloring. 

5. After striking out the skins should be shaved, remember- 
ing during the shaving to protect the grain from stain or 
grease. 

6. The shaved skins can then be stained, fat-liquored, col- 
ored, set out, etc., dried, staked and finished in the ordinary 
way. 

TANNING SHEEP SKINS BY THE CHROME PROCESS. 

The Martin Dennis Chrome Tannage Company give the fol- 
lowing directions for preparing sheep and lamb skins for tan- 
ning by their one-bath process : 

1. The skins should be wrung or pressed to remove the 
animal grease, and then milled in a solution of common salt 
and water to open up and soften the fibres of the skin. 

2. If pickled skins are to be tanned, it is better to remove the 
pickle before commencing the tanning operation, with a drench 
of " C. T. Bate," or, if this preparation is not at hand, with a 
drench of bran and salt. 

3. The skins should then be given a bath of alum and salt in 
the proportion of 1 to 2 lbs. alum and about 5 lbs. salt to the 
dozen skins. The use of alum and salt, however, is optional. 
The object in using it is to keep the skins open and plump, to 
prevent them from drawing on the grain, and to keep the skins 
during the process of tanning in such a condition that they can 
be worked and set out with a slicker after being tanned, without 
having the spring to the leather already referred to. From 
this point the tanning of sheepskins is the same as the tanning 
of calf and goat skins above given. 

SOME PATENTS . FOR CHROME TANNAGE. 

It is now an established fact that chrome-tanned leather has 
secured a recognized place as an important article of pro- 
duction, and when its peculiar and superior qualities become 
more generally known to the public, the demand for this 
mineral-tanned leather will largely increase. Believing as we 



" CHROME," OR MINERAL TANNAGE. 307 

do that chrome leather is a thing that has come to stay, and 
feeling confident that the future is full of promise to the 
tanner who masters the art of producing this leather, we 
have obtained the following information regarding the Dennis 
"one bath" process of chrome tannage, in order that our read- 
ers may become acquainted with one of the methods of chrome 
tanning which is already largely in use and which has found 
favor with tanners all over the world. 

For four years tanolin has been sold in the market as a 
tanning material, and during that time it has achieved a wide 
reputation and reached a large sale. This is not to be won- 
dered at, because the various "two-bath" methods of chrome 
tanning are more or less complicated, perplexing and uncer- 
tain, and the desirability of obtaining an easier, simpler and 
more certain method was conceded on all sides. The tan- 
olin without doubt accomplishes this, and removes the difficul- 
ties inherent in other systems of chrome tanning to a remark- 
able degree, affording the tanner a method of changing from 
" the old to the new," which is simplicity itself. It may be 
said that the "one-bath" system opens up a much wider appli- 
cation of the chrome tannage, and at present it seems safe to 
predict that at no very distant day nearly all classes of leather 
will be tanned with chrome. 

The German tanners have taken hold of the matter of chrome 
tanning with great earnestness and have applied it to the pro- 
duction of a great variety of leathers. The German is by na- 
ture an investigator and is, moreover, endowed with an amaz- 
ing degree of patience and perseverance ; and the consequence 
is that when he takes up with a new thing he turns it upside 
down and inside out until he discovers all there is to it, and if 
it proves to have merit, he is quick to adopt whatever may be 
to his profit and advantage. So it has been with tanolin, the 
German recognizing from the start that the " one-bath" method 
of chrome tanning had many advantages over the complicated 
"two-bath" system. The English are also waking up to the 
possibilities of mineral tannage and are giving considerable 



308 THE MANUFACTURE OF LEATHER. 

attention to it, though they have not accomplished so much in 
this direction as the Germans. 

Until recently the chrome tannage has been almost entirely 
confined to the production of light shoe leathers from goat 
skins, but since the introduction of tanolin nearly all sorts of 
hides and skins have been tanned with chrome and finished in 
a great variety of ways for almost all the uses to which leather 
is put. It is interesting to note what has already been accom- 
plished with tanolin by clever, enterprising tanners. 

In view of the things already accomplished, it is difficult to 
foretell where these new and modern processes of tanning will 
lead us. Of one thing we are certain, and that is that it brings 
a benefit to all concerned ; to the tanner, because it enables 
him to produce leather cheaper and quicker ; to the consumer 
of leather, because he is furnished with a better and more dur- 
able article. 

THE DENNIS TANNING-LTQUOR.* 

This invention relates to a liquor to be used in the tanning of 
leather, and is described by Mr. Dennis as follows : 

It consists of a novel composition of matter in a liquor for 
tanning hides or skins in the method known as chrome tanning, 
and the method of making the same. 

In an application filed by me on the 3d day of October, 
1892, Serial No. 447,695, 1 have described and claimed the use 
of this liquor, which is the subject matter of this application, in 
tanning hides, and this application has, therefore, no reference 
to the methods of using this liquor, but relates solely to the 
composition of the liquor itself and the method of making it. 

It has long been known that chrome oxide has the property 
of combining with the hide gelatine to form an insoluble and 
non-putrescent body, and is, therefore, capable of converting 
hides into leather. It has only been during the last few years, 
however, that commercial leather has been made by the so- 
called chromic tannage, and there is still much room for im- 
provement. 

* Patented by Martin Dennis, Newark, N. J. United States Patent, No. 511,411. 



" CHROME," OR MINERAL TANNAGE. 309 

The difficulty standing in the way of the use of chromic 
oxide as a tanning agent has been its insolubility in water, and 
the consequent difficulty in getting the chromic oxide into inti- 
mate contact with the hide or skin to be tanned. Attempts 
have been made to overcome this difficulty by the use of 
chromic alum as a tanning agent, but without practical success. 
When chromic alum is used deoxidation or reduction is un- 
necessary, since the chromium exists in the alum in the form of 
an oxide ; but as chromic alum is a very stable body and gives 
up its chromic oxide with great difficulty, the process of fixing 
the hide gelatine by its use is exceedingly slow, unsatisfactory 
and expensive. This difficulty has in a measure been overcome 
in some processes, by impregnating the hide or skin with 
chromic acid and then reducing this chromic acid to chromic 
oxide in the substance of the hide by the use of some reducing 
agent, as, for example, sulphurous or oxalic acid, sulphureted 
hydrogen or protosulphate of iron. The chromic acid in these 
processes is usually introduced into the hides or skins by immers- 
ing them in a bath to which bichromate of potassium and a 
strong acid like hydrochloric acid have been added. Chromic 
acid, however, is a powerful oxidizing and corrosive agent and 
invariably does more or less injury to the hide or skin, and, un- 
less it is handled with very great skill and caution, will produce 
leather which will become hard and crack, and exhibit other de- 
fects. In fact the utmost care and experience often fail to pre- 
vent the finished leather from showing the destructive effect of 
this powerful corrosive agent. One of the probable causes of 
the deterioration of leather made by the use of chromic acid is 
that chromic acid itself appears to enter to a greater or less ex- 
tent into some sort of combination with the hide gelatine, in 
which combination it is not wholly reduced to chromic oxide by 
the sulphurous acid or other reducing agent employed, but 
after the leather is finished and placed upon the counter or 
manufactured into shoes, the oxidizing and destructive effects 
of the chromic acid become manifest by its losing its strength 
and suppleness and becoming hard and brittle and papery to 



3IO THE MANUFACTURE OF LEATHER. 

the touch. The unsatisfactory action of chromic alum in tan- 
ning and the destructive effect of the chromic acid upon the 
fiber of the hide and skin, therefore, renders it highly desirable 
to employ some method of chrome tanning which will be 
quicker and cheaper and more satisfactory than the use of 
chromic alum, and which will not necessitate the bringing of the 
hide or skin into contact with these strong and corrosive acids. 
The object of my experiments was, therefore, to discover some 
method of introducing chromic oxide to the hide or skin, to be 
tanned in a water-soluble, neutral and unstable combination, 
that is, to discover some chromic oxide compound soluble in 
water, in which the chromic oxide would be held loosely, that 
is, in an unstable combination, and which compound, when dis- 
solved, would be practically neutral, and I have succeeded in 
doing this by my invention, which I will now describe. 

It is well known that when to solutions of a number of the 
normal salts of chromium is added a quantity of a more power- 
ful base, a part of the acid which was combined with the chro- 
mium base is taken away and the chromium base is left in a 
combination which may be regarded as basic, that is, contain- 
ing two or more equivalents of the metallic base or oxide to 
one of the acid, and when in this condition the excess of the 
metallic base or oxide over what the acid would hold in the 
normal salt is readily yielded to any body having an affinity for 
it; that is, the excess of the metallic base over what would be 
present in the normal salt is held in an unstable combination 
with the normal salt. While this is a well-known chemical fact, 
it was not known prior to my discovery or invention that any 
commercial use could be made of this chemical property of the 
salts of chromium in chrome tanning. 

In preparing my tanning liquor according to this invention, I 
utilize this property of chromium salts. I have found chloride 
of chromium best adapted for my purposes, although other in- 
organic salts of chromium may be used with more or less suc- 
ces, and I prefer to use chloride of chromium in practicing my 
invention, and shall use it hereinafter in illustrating the same. 



"CHROME," OR MINERAL TANNAGE. 3 I I 

In practicing my invention, I first prepare a solution of com- 
mon chloride of chromium. This may be done by dissolving 
the commercial oxide of chromium in commercial hydrochloric 
acid, which has been diluted with an equal bulk of water, care 
being taken to use more chromic oxide than the acid will take 
up, in order that the resulting solution may be as nearly neutral 
as possible. About eight ounces of the commercial acid is 
sufficient to dissolve a pound of commercial oxide of chro- 
mium. When this reaction is complete I have the normal salt 
of chromium, known as the chloride of chromium, in solution. 
In order to render this normal salt of chromium a basic salt, I 
add slowly and carefully to this solution a solution of a more 
powerful base, continuing the addition to a point where the 
normal salt has been practically rendered entirely basic. This 
point will differ in different cases, depending in a measure on 
the strength of the solutions, but the addition should not be 
carried beyond the point at which the oxide of chromium be- 
gins to precipitate, and the amount of base to be added can be 
readily ascertained in each case by making a small experimen- 
tal mixture. I may use for this more powerful base any of the 
caustic alkalies or the carbonates of these alkalies, but I prefer 
to use either caustic soda or the carbonate of soda, or, as the 
latter is known in trade, "sal soda." And when this is used it 
may be added until rapid effervescence ceases. It usually takes 
about half a pound of sal soda crystals to each pound of 
chromic oxide, dissolved as above. When this reaction is 
complete, it will be found that the carbonate of sodium has 
changed the normal chloride of chromium into an oxy or basic 
chloride of chromium. This may be considered as consisting 
of a normal chloride of chromium and chromic oxide in a water- 
soluble combination, free chromic oxide, hydrated or otherwise, 
being insoluble in water. This oxy or basic chloride of chro- 
mium is a very unstable body, giving up its excess of chromium 
oxide whenever there is presented to it a body or substance for 
which chromic oxide has an affinity, as, for instance, hide gel- 
atine. There exists also in this solution, when the last reaction 



312 THE MANUFACTURE OF LEATHER. 

is completed, a quantity of chloride of sodium formed by the 
union of a part of the acid which was in combination with the 
chromium in the normal salt of chromium with the sodium base 
of the carbonate of sodium. This chloride of sodium serves 
the useful purpose of preventing the grain of the leather from 
drawing under the astringent effect of the chromium salt and 
facilitates the tanning action, and to further effect these pur- 
poses I also add to this solution a few pounds more of chloride 
of sodium (common salt). When I use any of the alkalies or 
alkaline carbonates that do not contain soda, I prefer to add to 
the solution common salt. When this has been done, my tan- 
ning liquor is complete and ready for use in the manner indi- 
cated in my aforesaid application. 

I am aware that others have added carbonate of sodium to the 
solution of a chromium salt, but in all cases where this has been 
done, only so much carbonate of sodium has been added as 
would serve to take up the free acid in the solution of the chro- 
mium salt, and thereby neutralize the solution ; and in no case 
has carbonate of sodium been added to the solution of the chro- 
mium salt in an amount sufficient to effect or change the chro- 
mium salt in any particular, or for that purpose, while in my 
invention that is one of the principal objects of adding the car- 
bonate of sodium, as my solution is practically neutral before 
its addition. 

The tanning liquor produced by this invention is cheaper and 
more quickly and easily used than a liquor made from chromic 
alum ; is practically neutral, has no corrosive action on the 
hides, and is free from all offensive odors, in these particulars 
as well as others being a marked improvement on all known 
tanning liquors. 

Tn the foregoing specification and in the claims to follow, the 
term basic is meant to include metallic salts, which contain 
more than one equivalent of the metallic base to one equiva- 
lent of the acid, as above described ; and in the claims, the term 
carbonate of sodium is meant to include its chemical equiva- 
lents for the purpose specified. 



"CHROME," OR MINERAL TANNAGE. 313 

The word " tanning" is meant to include all methods of fixing 
or rendering insoluble the so-called gelatine of the hides or 
skins, for the purpose of converting them into leather. 

My invention consists broadly in a method or process of 
making a tanning liquor containing a basic or oxy-inorganic 
salt of chromium and the product of that process. 

Specifically, it includes a method or process of making a tan- 
ning liquor containing a basic or oxy-chloride of chromium 
and chloride of sodium, and the product of that process. 

THE DENNIS PROCESS OF TANNING LEATHER.* 

This invention relates to the manufacture of leather. 

It consists of a novel method of fixing the so-called gelatin 
of the hide or skin by means of a metallic oxide, and has for its 
object the cheapening and simplifying of the process of making 
mineral tanned leather, as well as the improvement of the 
manufactured product, and is described as follows by Mr. 
Dennis : 

It has long been known that chromic oxide has the property 
of combining with hide gelatin to form insoluble and non- 
putrescent body, and is, therefore, capable of converting hides 
into leather. It has been but a few years, however, that com- 
mercial leather has been made by the so-called chromic tan- 
nage, and there is still much room for improvement in this 
kind of leather as placed at present on the market. In my 
process chromic oxide is presented to the hide gelatin in the 
state of a soluble combination in which it is so loosely held 
that it is readily given up to the gelatin, rendering the fixing of 
the latter both rapid and complete. The soluble combination 
which I use is designated by chemists as a basic or oxy salt. 
When to solutions of a number of the normal salts of chro- 
mium is added a quantity of a more powerful base, a part 
of the acid which was combined with the chromium base is 
taken away and the base is left in a combination which may be 
regarded as basic, that is, containing two or more equivalents 

* Patented by Martin Dennis, Newark, N. J. United States Patent, No. 495,028. 



3 14 THE MANUFACTURE OF LEATHER. 

of the metallic base or oxide to one of the acid. In this case 
the excess of metallic base over what the acid would hold in the 
normal salt is readily yielded to any body having an affinity for 
it. The effectiveness of my method, as far as the mere fixing 
of the gelatin is concerned, lies in bringing the latter in con- 
tact, in a neutral or nearly neutral solution, with a chromic 
oxide so held as to be readily taken up by the gelatin. This 
result is accomplished by solutions of the combinations which 
I have called basic salts ,of chromium, and they furnish the 
only practicable means of presenting to the hide gelatin, 
chromic oxide in soluble form and yet not in stable combina- 
tion with acids. When hides or skins, properly prepared, are 
treated with a solution of one of these basic chromic salts the 
gelatin quickly takes up the excess of the chromium base, (in 
combination with which it is insoluble,) and leaves only the re- 
maining normal salt in solution. 

Attempts have been made to use chromic alum for convert- 
ing hides into leather, but without practical success. When 
chromic alum is used, deoxidation or reduction is unecessary, 
since the chromium exists in the alum in the oxide form ; but 
as chromic alum is a very stable body, and gives up its chromic 
oxide with great difficulty, the process of fixing the hide gelatin 
by its means is exceedingly slow and unsatisfactory. 

The central idea upon which the practicable methods of 
chromic tannage, other than mine, are based, is to impregnate 
the hide or skin with chromic acid, and then to reduce this 
acid to chromic oxide in the substance of the hide, by means of 
some reducing agent, for example sulphurous or oxalic acid, 
sulphureted hydrogen or protosulphate of iron. The chromic 
acid is usually introduced into the hides or skins by immersing 
them in a bath, to which bichromate of potassium and a strong 
acid like hydrochloric have been added. Chromic acid, how- 
ever, is a powerful oxfdizing and corrosive agent, and invariably 
does more or less injury fo the hide or skin, and unless it is 
handled with very great skill and caution will produce leather 
which will become hard and crack and exhibit other defects. 



" CHROME, OR MINERAL TANNAGE. 3 I 5 

In fact the utmost care and experience often fail to prevent 
the finished leather from showing the destructive effect of this 
powerful chemical agent. 

One of the probable causes of the deterioration of leather 
made by the use of chromic acid is, that' chromic acid itself 
appears to enter to a greater or less extent into some sort of 
combination with the hide gelatin, in which combination it is 
not wholly reduced to chromic oxide by the sulphurous acid or 
other reducing agent employed, but after the leather is finished 
and placed upon the counter or manufactured into shoes, the 
oxidizing and destructive effects of the chromic acid become 
manifest, by losing its strength and suppleness and becoming 
hard and brittle and papery to the touch. 

It is true that the above method, as far as fixing the gelatin is 
concerned, although it is done in acid solution, is very effective. 
In fact it is, outside of mine, the only practical way known of 
occomplishing that result. This effectiveness is due to the fact 
that chromic oxide (which is the real fixing agent) is formed 
by the reduction of the chromic acid while in actual contact 
with the hide gelatin. Therefore the gelatin can take up the 
chromic oxide while in the so-called " nascent" state, and thus 
accomplish in a solution, what it could not easily do if the 
oxide were not formed in direct contact with it; for instance, 
as when the hide is treated with an acid or even neutral solu- 
tion of a normal salt of chromium. But the destructive action 
of chromic acid on the fiber of the hide or skin (particularly 
when the highest skill is not employed) renders it extremely 
desirable to use a method in which the hide is not exposed to 
the action of chromic acid or other destructive chemical agent, 
or to intensely acid solutions of any kind, but in which the 
chromic oxide is brought in contact with the hide gelatin in a 
nearly neutral and mild solution, and yet in a form in which it 
can be easily and quickly taken up. All this is accomplished 
by my method, which I will now describe. 

The salt of chromium which I have found well adapted for 
my purpose is the chloride, although other salts might be used, 



3 l6 THE MANUFACTURE OF LEATHER. 

and this I use to illustrate my process in the following descrip- 
tion : I first prepare a solution of common chloride of chro- 
mium. This may be done by dissolving the pigment known as 
chrome green, and which is hydrated oxide of chromium, in 
commercial hydrochloric acid which has been diluted with an 
equal bulk of water, care being taken to use more chromic 
oxide than the acid will take up, in order that the resulting 
solution may be as nearly neutral as possible. About eight 
ounces of the commercial acid are sufficient to dissolve a pound 
of commercial hydrated oxide of chromium. To this solution 
of chloride of chromium I add slowly and carefully a solution 
of a more powerful base, and for which purpose I prefer car- 
bonate of sodium, or as it is known in the trade, "sal soda," 
until precipitation of chromic hydrate begins, or if carbonate 
of sodium is used, until rapid effervescence ceases. It usually 
takes about one-half pound of sal soda crystals to each pound 
of chromic oxide dissolved as above. I now have a nearly 
neutral solution of oxy or basic chloride of chromium. It may 
be considered as consisting of the normal chloride of chromium 
and chromic oxide in soluble combination (free chromic oxide, 
hydrated or otherwise, being insoluble in water), and a quantity 
of chloride of sodium formed by the union of a part of the acid 
which was in combination with the chromium, with the sodium 
base of the carbonate of sodium, and which also serves a useful 
purpose, which will be mentioned later on. The hides or skins, 
after having been suitably prepared by soaking, liming, unhair- 
ing, bating, washing, &c, are immersed in the solution of the 
oxy or basic chloride of chromium prepared as above, and of a 
strength of about three gallons of the concentrated solution to 
one hundred gallons of water. To the solution is also added, 
besides that formed by adding carbonate of sodium to the solu- 
tion of chloride of chromium, a few pounds more of chloride of 
sodium (common salt) for the purpose of preventing the grain 
of the leather from drawing under the astringent effect of the 
chromic salt, and to facilitate the tanning action. The treat- 
ment of the hides or skins in the above solution is accomplished 



"CHROME," OR MINERAL TANNAGE. 317 

in a "paddle" or other equivalent apparatus, as it is quite 
necessary that they be frequently moved in order that the 
action of the chromic salt may be uniformly distributed. Ac- 
cording to the thickness of the skins and the strength of the 
solution, this tanning process requires from about ten to forty- 
eight hours. Ordinary goat skins for the so-called dongola 
leather do well by running them in the paddle during the day, 
then allowing them to stand over night in the liquor, and run 
the paddle about an hour in the morning, when the skins will 
be found well tanned. The strength of the chromic solution 
may be varied according to the thickness of the skins, and may 
be strengthened from time to time during the tanning operation 
if necessary. After the absorption of chromic oxide has ceased, 
and all the gelatin of the hide has been rendered insoluble by 
its combination with the chromic oxide, which condition is 
readily recognized by one familiar with leather making, the 
skins are washed in clean water, and are then agitated in a bath 
containing finely-divided carbonate of calcium or its equivalent. 

Instead of carbonate of calcium, carbonate of barium or the 
carbonates of lead, zinc, etc., may be used. When carbonate 
of calcium is used, the form known in commerce as whiting is 
well adapted. The object of agitating the skins with these car- 
bonates, which are insoluble in water, is that every kind of acid 
present may be neutralized without subjecting the skins to 
the action of an alkaline bath. The skins may now be again 
washed, after which they are ready for the so-called fat-liquor, 
for drying previous to dyeing, or for any other of the processes 
belonging to the currier's art. 

As my invention does not appertain to the beam-house work, 
by which the hides or skins are prepared for tanning, and 
which would be substantially the same for my process as for 
any other method of tanning or tawing, I will not specify any 
particular procedure for that part of the tanner's work. Neither 
is it necessary to give directions as to the treatment of the 
skins after they are removed from the bath of suspended car- 
bonate of calcium, for it is as various as the different uses to 



3 1 8 THE MANUFACTURE OF LEATHER. 

which leather is put, and does not belong to the realm of tan- 
ning proper, with which alone my invention has to do. 

Among the advantages possessed by my method may be 
mentioned the following : 

First, The tanning or fixing of the gelatin is effected entirely 
in one bath, instead, as in the old methods, of impregnating the 
skins with a chromic acid in one bath, and then reducing the 
chromic acid to chromic oxide in another bath. Thus the labor 
of one handling is saved. 

Second, The skins are not exposed to the destructive action 
of chromic acid, whereby the leather is stronger, has much more 
suppleness which it long preserves, shows a better grain, and 
does not become tinny or papery, as compared with the pro- 
duct of the ordinary method of chromic tannage. 

Third, There are no offensive or suffocating smells evolved, 
as when in the ordinary methods the chromic acid is reduced 
to chromic oxide by the use of sulphurous acid or sulphureted 
hydrogen. 

Fourth, Since my tanning bath is entirely non-corrosive, there 
is no danger of allowing the skins to remain in it too long, and 
not nearly so much skill and care are necessary as in the old 
methods. 

Fifth, Not only is there a saving in labor in my process, but 
my tanning bath is much cheaper than those of the old meth- 
ods, since the chromic oxide in my tanning bath costs much 
less as prepared by me than as prepared from bichromate of 
potassium and a reducing agent in the old methods. 

Sixth, The tanning is effected in my process in a bath, 
which is not strongly acid, as is always the case in the old 
methods, in which chromic acid is employed. This nearly 
neutral bath is of great advantage to the skins, and naturally 
assists the currier in the subsequent work of dyeing and finish- 
ing the leather. 

In the foregoing specification and in the claims to follow, the 
term basic is meant to include metallic salts, which contain 
more than one equivalent of the acid, as above described, and 



"CHROME," OR MINERAL TANNAGE. 319 

in the claims, the terms carbonate of calcium are meant to in- 
clude their chemical equivalents for the purpose specified. 

The word "tanning" is meant to include all methods of fixing 
or rendering insoluble the so-called gelatin of the hides or skins 
for the purpose of converting them into leather. 

The gist of my invention consists broadly in the use, as a 
tanning agent, of a basic or oxy salt of chromium. Specifically 
it includes the use as a tanning agent, a basic or oxy-chloride 
of chromium. It also includes a tanning bath prepared by 
adding to a solution of chlorfde of chromium, carbonate of 
sodium, or its equivalent, until the chromium salt is rendered 
basic. Further, it includes the use of a bath for tanning con- 
taining both basic chloride of chromium and chloride of so- 
dium. And lastly, it includes the process of subjecting hides 
or skins, in which the gelatin has been fixed by treatment with 
oxy or basic chloride of chromium, to the action of a neutraliz- 
ing bath of suspended carbonate of calcium. 

We are aware that by publishing the Dennis patents in full 
we have had to make many repetitions, but this could not 
be avoided, as we wished to make the chrome tannage fully 
understood, even if we have had to resort to tautology in 
doing it. 

F. E. Atteaux & Co., Boston, Mass., Sager Chadwick, Phila- 
delphia, Pa., Samuel P. Sadtler, Philadelphia, Pa., George W. 
Adler, who sold his patent to the Eureka Tannage Co., Phila- 
delphia, Pa., Hugo Schweitzer, New York, N. Y., have all re- 
cently invented one- and two-bath processes of chrome tannage. 

The patents issued to Augustus Schultz and William Zahn 
are given in full in the next chapter. 

CHARACTERISTICS OF CHROME LEATHER. 

Chrome leather has special and peculiar qualities which dis- 
tinguish it from all other kinds of leather, and these special 
features cause it to be a superior fabric for all the purposes for 
which leather is used. It has been often stated that chrome 
leather is waterproof, but this is not a proper term to use in 



320 THE MANUFACTURE OF LEATHER. 

connection with it; it should more properly be called non- 
absorbent. All kinds of leather produced with tannin absorb 
water readily, like a sponge, while chrome leather does not 
absorb the water but resists it or sheds it, like the feathers of a 
duck ; in fact it is a difficult matter to thoroughly wet through 
chrome leather when it is once dry. Again, water and air are 
the agencies in nature which promote decomposition and de- 
cay, and as tannin and hide substance are both organic mater- 
ials, and when combined, as is the case in bark-tanned leather, 
and subjected to a process of wetting and drying, such leather 
will eventually but surely deteriorate and become rotten. 

Chrome leather, on the other hand, being a combination of 
an inorganic material with the hide substance, and subjected to 
the same process of wetting and drying, shows no effect what- 
ever ; in fact, the oftener chrome leather is wet and dried the 
softer and more flexible it becomes. Even subjecting it to 
boiling water apparently has no effect upon it, while any sort 
of leather produced with tannin and placed in boiling water is 
utterly destroyed ; moreover, chrome leather is of much lighter 
weight than bark leather, and this is a decided advantage for 
almost all purposes for which leather is used. On this account 
considerable attention is being given to chrome leather by for- 
eign nations for military accoutrements. It seems that a 
soldier, fully equipped, carries six pounds and more of leather 
about him, and if this weight can be decreased one-half, his 
efficiency in marching will be increased ; if shoes can be made 
of less weight and more durable and afford complete protection 
for the feet from wet, such shoes will be a wonderful improve- 
ment over those at present in vogue. Harness made from 
chrome-tanned leather would be much lighter in weight, would 
not be affected by the perspiration of the horse, nor deteriorate 
by exposure to the weather. Chrome-tanned machine belting 
could be run in wet and damp places without fear of resulting 
damage or injury to the belt. Experiments made in the testing 
of chrome leathers indicate: ist, that chrome leather excels in 
strength ; 2d, that after reaching the stretching limit with a 



"CHROME," OR MINERAL TANNAGE. 321 

corresponding load, it possesses still a considerable degree of 
elasticity, which is of great value as regards the adhesion of 
belts to pulleys. One of the immediate possibilities of the 
future is that chrome-tanned gloves will be demanded by the 
public in preference to all others, simply because when such 
gloves become soiled they may be washed upon the hands with 
soap and water until cleansed, and when dried will be as soft 
and flexible as before washing. 

CURRYING CHROME LEATHER. 

In the currying of chrome leather some modifications both of 
methods and materials are required as compared with the usual 
methods employed on bark leather. In the first place chrome 
leather does not require nor will it absorb and hold as much 
oil and grease as bark leather ; in the second place, the chrome 
leather should be curried and stuffed soon after removal from 
the tanning bath, while it is still wet and before drying out, 
because if dried out immediately after tanning it is almost im- 
possible to wet down the leather thoroughly and uniformly, 
so that it can be properly stuffed and curried. Probably the 
most efficient means of incorporating oils and greases in chrome 
leather is by means of "fat- liquors," so called. There are vari- 
ous ways of preparing and using these fat-liquors, according to 
the quality it is desired to give to the leather. The fat-liquor 
in most general use is an emulsion of soap and oil, preferably 
a potash soft soap and a fine quality of neats-foot oil, used 
warm and in a dilute form and milled into the leather by means 
of a pin-mill drum. 

Other preparations are recommended, such as an emulsion 
of degras and egg-yolk, and also an emulsion of egg-yolk and 
olive oil. These fat liquors seem better adapted for lubricating 
the fibres and nourishing the leather than the hard greases and 
heavy fish oils which are used on bark leather. They impart 
to the chrome leather the necessary strength and flexibility 
without rendering it greasy and smeary. 
21 



322 THE MANUFACTURE OF LEATHER. 

TO PREPARE CHROME- TANNED LEATHERS FOR DYEING. 

A patent has been granted to E. Avellis and Emil Roster, 
both of Berlin, Germany, for an improved method of preparing 
chrome-tanned leather for dyeing. 

According to the patentees, their invention has for its object 
the preparation of chrome-dressed leather, so that it may be 
dyed in any desired shade or tint with aniline colors, and consists 
in first freeing the leather from acid, and subsequent treatment 
with materials containing tannin, although, in order to obtain 
a clear tint, it will be found expedient to re-tan the leather thus 
prepared with tartar emetic, or with preparations of the same. 

The following practical example will make the process 
clearer : 

In order to free 225 pounds chrome-tanned leather from 
acid, mix, in about 100 quarts of water, 7 pounds whiting 
and 5 pounds ordinary salt, washing the leather in this solution 
for about a quarter of an hour, until all trace of acid has been 
removed, which may be determined by means of blue litmus 
paper. Next, rinse in water to remove the chalk. 

Following the foregoing process, the leather, deprived of 
acid, is treated with materials containing tannin. When divi- 
divi is used, 2*^ pounds of the latter in a solution of 1 to 2 
deg. Beaume to 225 pounds leather is a very effective propor- 
tion, and a correspondingly weakened solution may be em- 
ployed for light tints. 

Although the leather thus prepared may be dyed at once, it 
is however, advisable, in order to obtain clearer tints, to first 
re-tan with tartar emetic. 

The proportions recommended for the purpose are : For 
chrome-tanned sheep leather and kid, 15 grains tartar emetic 
to 3 quarts liquor for each skin ; for calfskins, 22 to 30 grains to 
6 quarts liquor (according to size of skin) ; cowhides, 100 to 
150 grains for 10 to 18 quarts. The tan liquors are used at 96 
F., the leather being allowed to remain in the wheel or fulling 
mill from 5 to 8 minutes ; it is then rinsed in fresh water, and 
then dyed the desired color in vat or drum. 



" CHROME," OR MINERAL TANNAGE. 323 

DYEING CHROME LEATHER. 

Chrome leather is easily dyed, and takes all shades of color 
most readily. If the neutral basic aniline colors are used, it is 
necessary to mordant the leather with some wood-dye, and then 
color to shade with aniline. For very light shades a weak de- 
coction of sumac may be used ; for medium shades a fustic 
liquor, and for dark shades a mixture of fustic and logwood 
may be used as a mordant, 

It is said that the acid aniline colors dye directly without the 
use of a mordant ; very recently, it is claimed that the chrome 
leather may be dyed successfully with alizarine colors. 

In order to fix alizarine colors in leather, it is necessary to 
apply considerable heat; for this reason they are not applica- 
ble to the ordinary tanned goods. Chrome-tanned leather will, 
however, stand a high temperature without the slightest dam- 
age, and for this reason good results are to be had with aliza- 
rine dyes. 

The use of alizarine colors in powder form is not generally 
known to the leather manufacturers, but when it becomes so it 
will prove a great boon, as they produce full bright colors that 
are fast and dye very evenly. 

Alizarine dyes have a great afninity for the oxide of chrome, 
in fact, require a chrome mordant, viz. : bichromate of potash 
and an assistant of organic acid like lactic acid to produce the 
oxide of chrome. Inorganic acids, like sulphuric, muriatic, or 
even oxalic, should not be used, as they have a tendency to 
affect the leather, producing bad results. 

Lactic acid when free from adulterations, about 30 degrees 
strength and used with bichromate of potash, makes the best 
" all-round" mordant to be used on leather, regardless whether 
the same be tanned with chrome, vegetable material or alum, 
or whether the dye-stuff be wood, anilines, or alizarines, and the 
method of dyeing employed is that of coloring on the table, in 
the box, paddle or drum. 

The application of alizarine to fibres other than those of 
vegetable origin is of comparatively recent date, and even ten 



324 THE MANUFACTURE OF LEATHER. 

years ago alizarine colors on wool were practically unknown. 
When, however, through the breaking up of the alizarine syn- 
dicate, alizarine* was brought into the market at a low price, 
wool dyers began to direct their attention to this and allied 
coloring matter, with the result that at the present time large 
quantities of them are used in the production of fast shades on 
loose wool, stubbing and yarn. That their superiority over 
other coloring matters is recognized by merchants, and prob- 
ably also by the public, is revealed by the fact that special 
prices are sometimes quoted for alizarine-dyed goods, as distinct 
from such as are dyed with other coloring matters. 

The application of the alizarines in silk dyeing is of still 
more recent date, and although the demand has hitherto been 
restricted to embroidery, yarns, sewing silks, and stripes for 
trouserings, the colors have latterly been used for silk plush, 
for seals and for producing fast fancy shades. 

The usual method adopted in wool and in silk dyeing is to 
first mordant the material with salts of chromium, iron, alumin- 
ium or tin (for wool, chrome is principally employed). After 
washing off or soaping, the material is immersed in the cold or 
lukewarm dye-bath, and the temperature is gradually raised to 
the boil and kept at that point until the bath is exhausted. The 
actual formation of the color lakes only begins at 194 F., and 
is completed between this temperature and the boiling point in 
from twenty minutes to half an hour. 

In the case of leather dyeing with these materials this pro- 
cedure is, of course, impossible, except for chrome tanned 
leather, from the fact that leather tanned with organic tannins 
will become rotten if exposed to a higher temperature than 
about 122 F. for any length of time. The solution of this dif- 
ficulty has been found by H. Koechlin and E. Knecht, who 
adopt a principle previously applied to wool. They first pad 
the leather with a solution of alizarine rendered slightly alkaline 
with ammonia, and then develop in solutions of alumina, 
chromium, or iron salts. If the pieces are dried after having 
been padded in the alkaline color solution and are then printed 



"CHROME," OR MINERAL TANNAGE. 325 

with thickened acid or stannous chloride, a variety of white or 
colored figures can be obtained on colored grounds. If, for in- 
stance, the goods, padded in the ammoniacal alizarine solution 
and dried, are printed with stannous chloride and then passed 
through pyrolignite of iron, an orange pattern is obtained on a 
violet ground. 

In the practical application of this principle to leather dye- 
ing, the comparatively strong, slightly ammoniacal alizarine 
solution (or nitro-alizarine, a solution of the monosodium salt, 
as the case may be) is first applied to the leather by means of 
a brush or pad, and the color lake is then formed by a subse- 
quent treatment in the mordant solution. Since it has been 
found that ordinary alum or nitrate of iron is liable to precip- 
itate a considerable amount of unchanged alizarine in the 
leather, it is preferable to use these salts as basic as possible ; 
but it is evident that the process when properly applied, ensures 
the production of a large variety of useful and fast alizarine 
shades on leather without incurring any damage to the mate- 
rial, and this is one more victory to the credit of science in the 
art of leather manufacture. 



CHAPTER XXIII. 

KID OR MOROCCO LEATHERS. 

There has been a greater revolution in morocco manufactur- 
ing in ten years than in all the centuries of its existence. Skins 
were formerly tanned with sumac, gambier or alum. The new 
agent, chrome, was introduced in 1884. This was the most 
important event that ever occurred in the history of the trade 
— perhaps in any trade. From this material better kid was 
made than any that had been imported. Its use forthwith re- 
duced the import of foreign morocco seventy per cent. From 
being importers we became large exporters of this leather. 
The qualities of chrome-tanned kid, such as imperviousness to 
water, firmness and softness, together with the peculiarity of 
looking better in the shoe than before it was made up, caused 
its universal adoption. All its merits were examined and freely 
discussed in the meetings of the Morocco Manufacturers' Asso- 
ciation. The committee advocated its adoption and spent much 
time in seeking to remedy some of the early defects in the tan- 
nage. 

On January 8th, 1884, two patents were issued to Augustus 
Schultz, of New York City, by the United States Patent Office, 
for tawing hides and skins. These letters patent are Nos. 291,- 
784 and 291,785, and are later on described in this chapter. 
Augustus Schultz was, at the time application was made for 
these patents, an employee of the firm of William Pickhardt & 
Kuttroff, New York, N. Y., and at first lived in Hoboken, 
N. J., but moved to a house which Mr. Pickhardt had pur- 
chased at No. 135 East 15th St., New York, for the purpose of 
fitting up for patents which he possed for ventilating and heat- 
ing. His residence is now near Manassas, Virginia. He is 

(326) 



KID OR MOROCCO LEATHERS. 327 

€4 years of age. Mr. Schultz made all of his experiments in 
glass goblets, of large size, of which he had a half dozen or 
more. 

He knew of no tanner in those days except Julius Kuttner, 
in the employ of Booth & Co., of Gloversville, N. Y. Mr. 
Schultz asked Mr. Kuttner if he knew of anything that would 
be of advantage to the leather trade, and he replied that it 
would be desirable to find something that would replace the egg 
yolk which his firm was using for finishing their leather. Mr. 
Schultz tried to find a substitute for egg yolk; but this experi- 
ment was a failure, and Mr. Schultz then commenced the experi- 
ments in tanning leather in 1880, and he continued these ex- 
periments until his two patents were issued in 1884. 

The reason which Mr. Schultz gives for taking out two 
patents is that Dr. Antisell, who was that time Examiner in the 
U. S. Patent Office, would not allow hyposulphite of soda to 
come into the patent with the fumes of sulphur and the sul- 
phite of soda. 

Many tanners of kid leather use only the process described 
in patent No. 291,784, which provides for the use of hyposul- 
phite of soda. 

On the 15th day of June, 1891, Augustus Schultz sold, as- 
signed and transferred to Ludwig Roth all his interest in both 
of said patents; and on the 30th day of November 1891, Lud- 
wig Roth assigned said patents to Ferdinand Blumenthal, Lud- 
wig Roth and Julien S. Ulman, constituting at that time the firm 
of F. Blumenthal & Co., New York City and Wilmington, Del. 

On December 15th, 1891, the firm of F. Blumenthal & Co. 
was dissolved by mutual consent and by the retirement of Lud- 
wig Roth, and the two patents were transferred to the firm of 
F. Blumenthal & Co., composed of Ferdinand Blumenthal and 
Julien S. Ulman. On the 16th day of June, 1892, the firm of 
F. Blumenthal & Co. assigned the two said letters patent to 
Marcus Beebe and Robert H. Foerderer, who in turn, on the 
30th day of August, 1892, assigned the two said letters patent 
to the Tannage Patent Company, of Philadelphia, Pa., who still 



328 THE MANUFACTURE OF LEATHER. 

own them. The patents will expire on the 8th day of January, 
1901. 

The superior qualities of chrome tanned leather are its great 
strength, its insolubility in water, its susceptibility of being 
finished in various ways and colors, and its excellent wearing 
qualities. Leather made by the chrome process, while being 
exceedingly soft and pliable, is less liable to stretch than leather 
made by other tannages, in other words, shoes made of chrome 
leather, after being worn for any length of time, will retain their 
size and shape to a remarkable degree. This was not the case 
with leathers tanned by any of the well-known processes prac- 
ticed prior to the date of the Schultz patents. There are reas- 
ons which make it of great advantage to the tanner to use the 
chrome process. 

William M. Norris says: "The class of goods which was 
turned out up to the introduction of the Schultz patents 
ceased to be called for by shoemakers, and manufacturers 
were obliged to turn their attention to the newer mineral tan- 
nages with a glazed finish. French kid was the standard of 
excellence, and the aim of experimenters was. to reproduce this 
as nearly as possible. The methods of tanning this leather in 
France, as nearly as could be ascertained, were to tan or taw 
the skins with alum, salt, flour and egg yolk, dry them out, and 
lay them away for six months or so before finishing. This 
'ageing' or 'laying away' was essential in order that the alum 
should 'set' and be rendered somewhat insoluble, or, in other 
words, that the soluble sulphate of alumina in the alum should 
be converted into the insoluble oxide. 

" This process was altogether too slow for the American 
manufacturer, and also the price leather tanned by this process 
commanded was not sufficient to recompense him for the large 
stock necessarily carried and the large capital required to con- 
duct the business. 

"About this time it was discovered that gambier used in 
connection with alum produced leather that could be finished 
at once, without laying the stock away for several months, and 



KID OR MOROCCO LEATHERS. 329 

also that the finished product was strong, handsome, and would 
stand more wear than the imported article. 

"This alum and gambier, or so-called 'Dongola' tannage, is 
entirely an American process, and has been brought to great 
perfection during the last few years. 

"While French kid was only made into high-priced shoes, 
which were naturally taken care of by the purchaser and worn 
in the house or only out-doors in fine weather and on city 
pavements, the American Dongola leather, owing to its lower 
cost, was made into all grades of shoes, some of which sold at 
a very low price and which were subjected to hard wear during 
inclement weather, often in muddy country roads and on rough, 
uneven pavements. This soft kid leather is not adapted to 
rough wear and did not give satisfaction when subjected to it. 
Shoes, when soaked, were apt to dry out hard and unpliable, 
and the grain was apt to peel off when brought in contact with 
rough stones or subjected to the constant wear of ladies' dresses. 
Shoe manufacturers became more and more exacting in their 
demands. They wished a gloss or finish that was water-proof, 
leather that would stand a good wetting without injury, and 
which had a tougher grain, and so there has been a marked 
falling off in the demand for ' Dongola' leather, and the product 
which now seems to fill the requirements of shoe manufacturers 
is produced by the so-called 'acid' or 'chrome' process of tan- 
ning. 

"We are indebted for this tannage, not to the numerous 
inventors and their impracticable processes, but to a young 
morocco manufacturer of Philadelphia. This gentleman had in 
his office a few dozen skins of a celebrated French manufac- 
turer. From frequent examinations of these skins he became 
convinced that there was an indescribable something about 
them that was entirely wanting in the domestic article. He 
endeavored to produce stock like it, and was understood by 
his neighbors to be using chrome as a tanning agent. For 
several years his efforts resulted in few successes and many 
discouragements, but finally he perfected all the difficult and 



330 THE MANUFACTURE OF LEATHER. 

minute details of his process, and was enabled to place a most 
superior product on the market. He ran his factory to its 
utmost capacity, and then moved to a larger and more com- 
modious one, where, to meet the demands of the trade, he 
constantly increased his production until it reached the enor- 
mous and unprecedented quantity of a thousand dozen skins a 
day. 

" If it had not been for the wonderful success of this Phila- 
delphia manufacturer, little would be heard of chrome or 
chrome-tanned leather to-day. 

" It has long been known that the salts of chromium have a 
strong affinity for gelatine, and form with it insoluble com- 
pounds, and therefore have tanning power ; but it was not until 
very recently that these salts of chromium were employed in 
the manufacture of leather with success. 

"All the salts of chromium may be used for tanning, as well 
as bichromate of potash, or magnesia, chromic acid, and 
bichromate of ammonia, aluminium and iron. 

"But so far manufacturers have generally confined their 
attention to bichromate of potash, as this is the most widely 
known of the chromium salts. 

" Potassium bichromate, generally known as ' bichromate ' or 
1 bichrome,' is manufactured in large quantities from chrome 
iron ore, or chromite, by the action of some oxidizing agent. 
This important mineral is found in large quantities near Balti- 
more, Md., in Norway and the Shetland Islands off the coast of 
Scotland, as well as in Asia Minor, Siberia and Australia. 

" Bichromate of potash crystallizes in anhydrous, fine red, 
square tables, specific gravity 2.7, and is of intensely metallic 
taste ; 100 parts of water at 3 2° F. dissolve 4.6 parts, at 6o° F. 
12.4 parts, and at 21 2° (boiling) 94 parts. 

PREPARING THE SKINS. 

When the dry goat-skins are removed from the bales, they 
are placed in the "soaks," which are vats containing clear cold 
water, and remain for from three to five days, the period of 



KID OR MOROCCO LEATHERS. 33 1 

course depending upon the condition of the skins, the hardest 
requiring a longer soaking than those that are softer. Five 
pounds of borax is added to each 1,000 gallons of water in the 
"soaks;" the borax being first dissolved in boiling water and 
then thoroughly stirred into the water of the " soaks." (See 
Chapter VI.) 

From the "soaks" the skins are removed either with hooks 
or tongs, and placed, usually 150 to 200 at one time, in the 
" pin-mill," which is a softening contrivance, and when suffic- 
iently softened the skins are next placed in the "limes." 

In many kid tanneries it is the custom to break or flesh the 
skins after they come from the " soaks," the machine shown in 
Fig. 95 being especially adapted for this purpose. 

Fig. 94 shows a view of the lime-vats, in a kid or Morocco 
tannery, and over one of the pits is shown a pile of skins which 
have been removed therefrom and placed upon planks to drain, 
while in the background is shown the " wash-wheel." Above 
each lime-vat there is a small blackboard upon which are marked 
in chalk the number and kinds of skins in each vat and the date 
on which they were put in. 

In large Morocco tanneries usually 1350 South American 
goat-skins are limed at the same time, and about 600 glove- 
calf, and 800 glove-sheep are placed in separate vats at once. 

The goat-skins remain in the "limes" about 14 days, glove- 
calf 12 days, and glove-sheep 8 days. The lime is mixed with 
red arsenic, as this agent losens the fine hairs better than any 
other. (See Chapter VII.) 

They then go on to the unhairing machine shown in Fig. 95, 
or to the unhairing beams, and are unhaired by hand, and one 
man will " unhair, flesh, and slick" about eighty skins per 
day. 

The machine shown in Fig. 95 can be used not only for un- 
hairing, but for breaking, fleshing and slating, and is equally 
adapted to goat, sheep, calf and kangaroo skins. It requires 
but one operator to each machine, and is economical in space 
and power required to operate it, and is guaranteed by its 



332 



THE MANUFACTURE OF LEATHER. 




KID OR MOROCCO LEATHERS. 



333 




334 THE MANUFACTURE OF LEATHER. 

builders, Vaughn Machine Co., Peabody, Mass., to do better 
work than can be done by hand or any other machine, and at 
the same time quantity enough to suit anybody, whether doing 
a large or small business. 

The Vaughn Machine Co. have thoroughly remodeled and 
perfected this machine in every detail. It is the only machine 
that will break or flesh skins in the hair from the soalcs be- 
fore being limed, which is an important thing to be done on all 
hard-natured or very fleshy skins, as thereby the scale and all 
superfluous flesh are removed, the skin thoroughly spread out 
and softened, and put into the most desirable condition to go 
into the limes. For unhairing it is very useful and profitable, 
as it will do an immense quantity of good work and without 
any damage whatever. For fleshing it is perfection, doing the 
work cleanly, evenly, and without any tearing or damage 
whatever ; the machine being so completely under the control of 
the operator that there is no danger in fleshing the most delicate 
skin, while on heavy stock it will cut down as much as is 
wanted ; therefore, making a great saving in tanning materials 
and shaving. For slating nothing can equal it, as the skin is 
being worked both lengthways and sideways by the cylinder at 
the same time, the dirt and fine hairs being thoroughly worked 
out and with absolutely no danger of grain scratches. This 
invention is a great labor and time saver. It is operated by 
one man, and performs the work of a dozen men. 

It is impossible to do any of the above-named work in any 
other way nearly as well as it can be done with this machine. 
The principle of the machine is an absolute guarantee of this, 
for the bed or beam on which the skin lies is carried over and 
back under the cylinder, so that it is worked both ways at one 
operation, and also that the operator sees just what is wanted to 
be done to each skin as it goes through, and then just how the 
work has been done as it returns to him. This insures perfect 
work on each skin before it leaves the machine. 

After being unhaired the skins are placed in a mill and thor- 
oughly washed with water and borax to free them from adher- 



KID OR MOROCCO LEATHERS. 335 

ing lime and dirt, and are next placed in the slightly-heated 
bate of dog or pigeon manure, in which they remain over night. 
(See Chapter IX.) 

The character of the leather produced by any of the chrome 
processes is greatly influenced by the previous treatment of 
the raw pelt. It must be remembered that all chrome tannage 
is necessarily light-weighing and empty, since the quantity of 
chrome oxide fixed is far smaller than in the case of vegetable 
tannins. It is, therefore, of great importance, if plump leather 
is required, that the natural substance of the hide or skin 
should be spared as much as possible in liming and bating or 
puring. The liming is best accomplished in ' arsenic limes ' 
in the case of light goods, or with the addition of yi pound or 
more of sulphide of sodium per hide in ordinary limes. Where 
a smooth grain and plump leather is important, chemical delim- 
ing is much to be preferred to the use of fermenting bates 
or drenches. Use a solution of 2 per cent, boracic acid and 
i per cent, of good carbolic acid in water, frequently after first 
'pulling down' by paddling in warm water to which about ^ 
pound of sulphuric acid and 2 ounces of sal-ammoniac is added 
per 100 pounds of wet pelt. When the goods come out, this 
solution should test slightly alkaline to red litmus paper, and 
if this is not the case sufficient ammonia should be added to 
make it so, and the goods paddled in it another half hour; and 
in future operations the amount of acid must be reduced. The 
boracic acid bath may be used repeatedly ; goods will keep in 
it even for months without change. If limey goods are treated 
in it without previous ' pulling down,' it may be made slightly 
acid to litmus paper with hydrochloric or sulphuric acid each 
time before using, the strength being also maintained by small 
additions of boracic and carbolic acids. In this solution the 
goods become quite free from lime, but remain pretty plump 
and full, and if tanned in chrome liquor which is not too strong 
at first, and without too violent motion, remain perfectly smooth 
in the grain. 

Upon removal from the bate the skins are "slated," which is 



336 THE MANUFACTURE OF LEATHER. 

the removal of the fine hair remaining upon the skins after the 
unhairing operation. The machine shown in Fig. 95 can be 
used or the hand method may be employed; the "slater" is a 
tool closely resembling a " slicker," but the edge of the 
"slater" is ground sharp. 

The skins are now passed into the bran drench, which is 
composed of bran and water, slightly heated, and in this they 
remain usually over night and are then finally washed with 
borax water. 

TAWING. 

If the skins are to be tawed according to the Schultz patent, 
they are immersed after the final washing with borax and water 
in a bath containing about five per cent, of the weight of the 
skins of bichromate of potash, and about two per cent, of hydro- 
chloric acid, since this amount of acid is sufficient to enable the 
skins to absorb the liquor; the skins are placed in a reel, with 
sufficient water to enable them to freely rotate by means of the 
action of the paddle-wheel ; the skins are left in this solution 
until this yellow liquor has thoroughly penetrated the skins, 
and have assumed an even yellow color all the way through, 
which is determined by cutting pieces from the thickest part 
of the skin, and when this even yellow color shows evenly 
through the skins, they are ready to receive the second bath. 
After removing the skins from the first bath, the skins are 
allowed to drain, or, in order to expedite matters, the surplus 
liquor is sometimes pressed out before putting them into the 
second bath. A bath is then prepared of about ten per cent, 
of hyposulphite of soda of the weight of the skins, and about 
two and a half per cent, of hydrochloric acid, and sufficient 
water to enable the skins to float by the same mechanical 
means as described in the first bath ; the skins are placed in 
the second bath, and allowed to remain therein until they 
assume a whitish, bluish or greenish color all the way through. 
This is also determined by cutting pieces from the thickest part 
of the skin; and when the yellow color has entirely disap- 



KID OR MOROCCO LEATHERS. 337 

peared, the skins are done ; this completes the tanning. Some 
of the stock is put on the market with no further treatment 
other than mechanical. Some of the stock is finished in various 
ways, in black and fancy colors and dull and glazed surfaces, 
and any treatment subsequent to that of tanning is based 
entirely upon the result obtained for the purpose for which the 
leather is to be sold. 

Skins are frequently tanned in baths constituted in different 
proportions of the materials as given. The proportions are 
varied according to the character of the skins and the product 
desired. Sometimes as high as eight per cent, of the weight of 
the skins of bichromate of potash and five per cent, of hydro- 
chloric acid, and as low as three per cent, of bichromate of 
potash and one per cent, of hydrochloric acid. There is no 
necessary hard and fast rule that must be followed. 

Neither is there any hard and fast rule that must be followed 
in regard to the amount of water used, or in other words in re- 
gard to the degree of concentration of the baths. On this 
point the greatest latitude is permissible. As a matter of fact, 
tanners vary this according to the apparatus which may be 
most convenient for them to use ; when skins are treated in the 
first bath in a drum the liquor is very much more concentrated 
than when treated in a reel. In treating skins in a drum, the 
skins are placed in a drum together with the tanning liquor ; 
the drum is securely closed and then caused to revolve, and the 
action caused thereby causes the skins to be raised in the drum 
and then fall back, which has a pounding action upon the 
skins and causes any liquors that are present to be rapidly 
absorbed. In a drum, a comparatively small amount of liquor 
is used, because, if a large amount of liquor is used the 
mechanical action of raising the skins and allowing them to fall 
back would not take place, and the skins and the liquor would 
remain at the lowest point, while the drum would revolve with- 
out causing agitation of the mechanical action that would 
facilitate the absorption of the liquor by the skins. The reel 
is a vat made in a semi-circular shape, in the centre of the top 
22 



338 THE MANUFACTURE OF LEATHER. 

of which is mounted an ordinary paddle-wheel. In order to 
procure the mechanical action desired, it is necessary to use an 
amount of liquor in the reel such that the blades of the paddle 
extend a sufficient depth into the liquor. The action desired 
is to cause the skins to be constantly rotated or agitated in the 
liquor, in order that every part and portion of the skins may be 
brought in contact with the liquors, and that the skins should 
not remain in a folded position where the penetration might 
not be even and uniform. For the reasons given, it is custom- 
ary to use more liquor and the baths are less concentrated 
when treating skins in a reel than when treating them in a 
drum. The only difference in the two methods is that in the 
case of tanning in the drum penetration is accomplished 
quicker and in less time than when tanned in a reel. The re- 
sult in the product, however, is exactly the same. 

The reel and drum described above are well known forms of 
apparatus used by tanners for tanning hides and skins. The 
hydrochloric acid above mentioned is the same as muriatic 
acid, and ranges from twenty to twenty-two degrees and is 
added to the bichromate of potash after it has been thoroughly 
dissolved, which is done by heating the water and the above 
specified weight of muriatic acid is then poured into the vat. 
The second bath is prepared after dissolving the hyposulphite, 
the muriatic acid is added, usually two to two and a half pounds 
to one hundred pounds of skins, and after stirring this thor- 
oughly the skins are placed in this bath ; the acid being of the 
same degree as in the first bath. The hyposulphite of soda 
after dissolving and being placed in this bath can hardly be 
noticed ; as soon, however, as the muriatic acid is added the 
color changes to a bluish green and creates sulphurous acid 
which can be detected at once by the smell, and it is as much 
as one can do to stand it. This bath changes the color of the 
skins from a yellow to a bluish white. 

It is not known what the chemical reactions are which take 
place when the skins which have been treated in the first bath 
(patent No. 291,785) are subjected to the action of the second 
bath. 



KID OR MOROCCO LEATHERS. 339 

It is evident from the change in color that a change takes 
place in the condition of the chromium of the first bath ; it is 
evident that what the chemist calls a reduction takes place. 
Some oxygen is taken away from the chromium compound, 
and the yellow compound of chromium containing much oxygen 
is changed to a green compound which contains less. This is 
about as much as is definitely known with regard to the chemi- 
cal reaction. 

The bichromate of potash has no effect upon the skins what- 
ever, and the only object in soaking the skins in the bichromate 
of potash is to have the bichromate of potash in the proper 
place at the proper time when the actual process of tanning is 
to begin. The tanning always takes place in the second bath. 
Here certain chemical changes take place between the material 
contained in the second bath and the bichromate of potash and 
the skin. There is no special significance in the word " bath." 
" Bath " is nothing but a solution, and all you can say is that 
previous to the date of these patents, skins had been dipped into 
a solution of something else, such as chloride of barium. In 
this case these two substances acting upon each other, produced 
a yellow powder, consisting of chromate of baryta, which fills 
the pores of the skin. 

The essential discovery made by Schultz was that an im- 
proved leather resulted from the action of the agents which 
liberate sulphurous acid upon metallic salts, such as bichromate 
of potash in the pores of the skin. He further discovered that 
still better results could be obtained by selecting hyposulphite 
of soda as the agent to be used in connection with the bichro- 
mate of potash. 

It cannot be determined exactly what the chemical reactions 
are which take place in the skins, when a bath containing 
sulphurous acid acts upon the bichromate of potash, and when 
a bath containing hyposulphurous acid acts upon the bichro- 
mate of potash. Sulphurous acid is one thing ; hyposulphur- 
ous acid is another. It is true that hyposulphurous acid under- 
goes decomposition and produces sulphurous acid, but that is 



340 THE MANUFACTURE OF LEATHER. 

not all it produces. It produces finely divided sulphur, and 
it is very probable that the action of the hyposulphite of soda 
involves more than the action of sulphurous acid alone. At 
all events, it is said to give better results in practice, so there 
must be some advantage in it even though it may not be 
known what chemical actions occurs. 

It is known that hyposulphurous acid will often accomplish 
results in chemical reactions which sulphurous acid alone will 
not accomplish. 

The operations involved in carrying out the process set forth 
in patent No. 291,784 are the same as in patent No. 291,785 
until we come to the preparation of the second bath described 
in the last mentioned patent. In this case the skins coming 
from the first bath are treated in a second bath, which con- 
sists of a solution capable of evolving sulphurous acid, such, 
for instance, as a solution of sulphite or bisulphite of soda, to- 
gether with some acid stronger than sulphurous acid, such as 
hydrochloric acid. The skins are allowed to remain in this bath 
until the change in color induced by the liberated sulphurous 
acid, (and which may be to a whitish or blush or greenish color 
according to the thickness of the skins, and consequently the 
time required to complete the action,) has penetrated through 
them. They may then be removed and finished after the 
ordinary manner. 

Some people have regarded the two patents above men- 
tioned issued to Augustus Schultz as deficient or even partially 
misleading in their descriptions. This is not so, as the direc- 
tions given are sufficiently full, clear and exact to enable any 
person skilled in the art to which the patents relate, to success- 
fully carry out the processes, and result in the production of a 
useful product. Any person skilled in the art, upon taking up 
these patents with a desire to put them in practical operation, 
would have no difficulty in understanding either the object at 
which they aim or the means set forth for the attainment of 
that object, or of the materials which may be used, or of the 
manner in which they may be employed. 



KID OR MOROCCO LEATHERS. 341 

In tanning goat-skins for kid leathers the skins remain in 
the first bath for about one-half day, and sometimes longer, if 
upon examination they were found to be not thoroughly tanned ; 
this examination being made by cutting the neck of the skin 
and seeing that no animal or raw material is left. 

The skins are left in the second bath until no show of bichro- 
mate or yellow is apparent. This process, by some tanners, is 
applied to the skins in the afternoon, and they are allowed to 
remain in the liquor of the second bath over night. Sometimes 
the skins are needed as quickly as possible, stock that has been 
actually sold or is needed for order is required, and instead of 
leaving the skin in the second bath over night, they are washed 
and rushed right along. The time that the skins remain in this 
bath, under such circumstances, is only for a few hours, the 
time depending of course upon the thickness of the skins under 
treatment. 

It has been demonstrated in practice that the use of sulphuric 
acid in the first bath and muriatic acid in the second bath 
would not prevent the carrying out of the Schultz process and 
making, by the aid of it, leather. 

This was tested practically by Professor Samuel P. Sadtler 
on January 4, 1894, at the tannery of Burk Bros., in Philadel- 
phia, Pa. He took a goat skin from the regular stock of pre- 
pared skins the skin weighing about twelve ounces. It was put 
in a bath of one hundred and twelve fluid ounces of water, three- 
quarters of an ounce of bichromate of potash in crystals, and 
one-half an ounce of strong sulphuric acid. The skin was 
entered at 11 : 50 a. m. at a temperature of 87 degrees F. for 
the bath. It was taken out at 3:25 p. m. after testing it for 
penetration in the usual manner. It was then struck out or 
freed from excess of moisture, and at 3 : 45 p. m. it was entered 
into a bath of hyposulphite of soda, one and three-quarter 
ounces, and one-half an ounce of muriatic acid of 21 Baume, 
dissolved in the same amount of water as that of the first bath. 
It was taken out after testing it for completion of the reaction at 
5 : 15 p. m., and was struck out. It was then put in freshwater 
over night. The result was good merchantable leather. 



342 THE MANUFACTURE OF LEATHER. 

The sulphuric acid of commerce usually contains a percent- 
age of hydrochloric acid sufficient for the work. 

In patent No. 291, 785 Mr. Schultz says: "An aqueous 
solution of sulphurous acid may be used." This undoubtedly 
means that in place of the two chemicals which are first pre- 
scribed as to be taken for the evolution of sulphurous acid, an 
aqueous solution of sulphurous acid could be taken of such a 
character as to accomplish substantially the results intended by 
the use of the mixed sulphite of soda and muriatic acid. 

Strong acid solutions would undoubtedly have an injurious 
effect upon the hide, of course that injurious effect would con- 
tinue into the leather produced. The skins would be swollen 
very rapidly in a relatively strong acid bath, and in that swollen 
condition the penetration of the bichromate salt, if the first bath 
be referred to, or the penetration of the chemicals of the second 
bath, equally would be hindered to a very considerable degree ; 
and at the same time, in addition to this swelling or " plump- 
ing," as it is termed, the acid is steadily disintegrating the 
fibre, acting upon the connective tissue of the hide, as it is 
termed. 

The plumping is a surface indication of the effect of the acid, 
and it undoubtedly preceded the other effect, that is, opening 
up or partially dissolving the connective tissue ; and while some 
plumping always takes place at stages of the tanning proceeses, 
excessive plumping is to be avoided, and in this case it is 
especially to be avoided, for the reason that it would prevent 
the penetration of the salts which are to be the effective tanning 
agents in the Schultz process. 

When a skin is introduced into an acidulated bath and the 
skin plumps, that bath contains too much acid. This may be 
noticed in the difference between the effect of neutral bichromate 
of potash solution and acidified bichromate of potash solution. 
In the neutral bichromate of potash solution the skin retains 
for a long time the soft, slimy feeling of the hide, and in the 
acidified bichromate of potash solution even with very small 
amounts of acid, there is a distinct surface roughening which 



KID OR MOROCCO LEATHERS. 343 

might be termed an incipient plumping, but which has no 
notable effect in the way of injury. 

The tan vat used in the two-bath method of chrome tannage 
is 7 feet long, 5 feet 6 inches wide, and 5 feet deep. Semi- 
circular to within 1 foot of top, where it is plumb up. Over this 
vat there is a revolving wheel 5 feet 6 inches long and 3 feet in 
diameter. This wheel has 7 wings in it; they are 2 inches 
thick and 9 inches deep. 

There are at least two of these vats in each morocco factory 
where the chrome process is used, that is, the two-bath process. 

SPECIFICATION OF SCHULTZ'S FIRST PATENT (NO. 29 1, 784). 

This invention, says Mr. Schultz, relates to a new process for 
tanning hides or skins, said process consisting in subjecting said 
hides or skins to the action of compounds of metallic salts — 
such as bichromate of potash — and then treating the same with 
hyposulphite of soda, by which term is understood that salt 
which is more recently sometimes called " thiosulphate of 
soda" (Na. 2 S 2 3 ). 

In carrying out my process, I unhair the raw hides and pre- 
pare them in the same manner in which they are made 
" ready " for tanning. If the hides have not been pickled, I 
subject them to the action of a solution of bichromate of potash 
in the presence of an acid, such as hydrochloric acid, or, if the 
hides have been pickled, they may be treated in a solution of 
bichromate of potash in water without the addition of an acid. 
In this solution the hides are left for a shorter or longer time, 
according to their thickness and to the strength of the solution 
employed. A skiver or the face of a sheepskin can be done in 
a strong solution, as above described, in about fifteen minutes, 
while a full skin "roan" would require in the same solution 
about one hour. I call the solution "weak" if it contains 5 
per cent, or less of the weight of skins of bichromate of potash, 
and I call the solution " strong " if it contains more than 5 per 
cent of bichromate of potash. It is not material, however, how 
strong the solution is. The skins are completed if small pieces 



344 THE MANUFACTURE OF LEATHER. 

cut from the thickest part of said skin show that the solution 
has entirely penetrated. The skins are then ready to be taken 
out, and after the adhering liquor has run off, the skins are in- 
troduced into the second solution, which consists of hyposul- 
phite of soda dissolved in water, and adding an acid such as 
hydrochloric acid. The solution may be strong or weak of 
hyposulphite, and the quantity of acid used at first may be less 
than requisite to split up the entire quantity of hyposulphite, 
and more acid may be added if the skins show that more is re- 
quired, which is indicated by the color of the skins. When 
they are done they show a whitish, bluish or greenish color, 
according to the time they are kept in the hyposulphite solu- 
tion. A skiver which has first been exposed to the action of 
the bichromate for fifteen minutes will be ready by remaining 
in the hyposulphite solution about twenty minutes. For thicker 
skins a proportionately longer time is required. For some skins, 
such as calf or steer's skins, it is desirable that the same, after 
having been drawn from the second or hyposulphite solution, 
shall be returned to the bichromate solution, which imparts 
to them a brownish color, and leaves them in a favorable 
condition to be colored black. The coloring can be done 
after the skins leave the hyposulphite solution, and after 
they have been exposed the second time to the bichromate 
solution. The leather coming from the hyposulphite solution 
is especially adapted for light or dark colors, and by proper 
dyeing methods better and brighter colors can be produced 
than on leather done by tanning. After the leather is treated 
in the manner above indicated, it may be colored, soaped and 
greased in the usual way. Leather can also be made by re- 
versing the operation and first soaking the hides in a solution 
of hyposulphite of soda, and then exposing them to the action 
of the bichromate solution. By using the solutions indicated 
at a heat of 8o° Fah., the process will be done in a shorter time 
than if the solutions are used cold. By my process the gelatine 
contained in the hides is rendered insoluble by means not in- 
jurious to the leather. If leather made by tannin is put in a 



KID OR MOROCCO LEATHERS. 345 

strong soda solution, the tannin is extracted and a dark-brown 
liquor formed. If leather made by my process is put in a 
strong soda solution, the liquor obtained shows only a little 
milky color. Leather made by my process is very strong, soft, 
elastic, and my process is applicable to hides or skins of every 
description. 

SPECIFICATION OF SCHULTZ'S SECOND PATENT (NO. 291,785). 

This invention, says Mr. Schultz, relates to the new process 
for treating hides or skins, said process consisting in subjecting 
said hides or skins to the action of a bath prepared from a 
metallic salt — such as bichromate of potash — and of then treat- 
ing the same with a bath containing sulphurous acid. 

In carrying out my process I unhair the raw hides and pre- 
pare them in the same manner in which they are made ready 
for tanning. If the hides have not been pickled, I subject 
them to the action of a bath of bichromate of potash in an acid,, 
such as hydrochloric acid ; or, if the hides have been pickled, 
they may be treated in a solution of bichromate of potash in 
water without the addition of an acid. In this solution the 
hides are left for a longer or shorter time, according to their 
thickness and to the strength of the solution employed. A 
skiver or the face of a sheepskin can be done in a strong solu- 
tion, as above described, in about fifteen minutes, while a full 
skin "roan" would require in the same solution about one 
hour. I call the solution weak if it contains 5 per cent, or less 
of the weight of the skins of bichromate of potash, and I call 
the solution strong if it contains more than 5 per cent, of 
bichromate of potash. The skins are done if small pieces cut 
from the thickest part thereof show that the solutions have 
entirely penetrated. The skins are then ready to be taken out 
of the solution, and, after the adhering liquor has run off, the 
skins are introduced into the second bath, which consists, by 
preference, of sulphite of soda dissolved in water, to which an 
acid — such as hydrochloric acid — should be added, in order to 
set free the sulphurous acid. The hydrochloric acid or its 



346 THE MANUFACTURE OF LEATHER. 

substitute may be added to the bath in a free state or through 
the medium of skins previously pickled, such skins being im- 
pregnated with the proper acid. The solution may be strong 
or weak of sulphite, and the quantity of acid used may be in- 
creased if the skins show that more is required, which is 
irfdicated by the color of the skins. When the skins are done 
they show a whitish, bluish, or greenish color, according to the 
time they are kept in the sulphite bath. A skiver which first 
has been exposed to the action of the bichromate bath for 
fifteen minutes will be ready by remaining in the sulphite bath 
about twenty minutes. For thicker skins a proportionately 
longer time is required. 

For some skins — such as calf or steer skins — it is desirable 
that the same, after having been withdrawn from the second or 
sulphite bath, shall be returned to the bichromate bath, which 
imparts to them a brownish color and leaves them in a favor- 
able condition to be colored black. The leather coming from 
the sulphite bath is especially adapted for light and also for 
dark colors, and by proper dyeing methods better and brighter 
colors can be produced than on leather done by tannin. After 
the leather is done in the manner above described, it may be 
colored, soaped and greased in the usual way. 

Leather can also be made by reversing the operation and first 
soaking the hides in a sulphite bath, and then exposing them 
to the action of the bichromate bath. By using the baths de- 
scribed at a heat of about 8o° Fahrenheit, the process will be 
done in a shorter time than if the baths are used cold. 

Tawed leather made by my process is very strong, soft and 
elastic, and my process is applicable to hides or skins of every 
description. 

Instead of using sulphite of soda, I can use other sulphites 
or bisulphites in presence of an acid or an aqueous solution of 
sulphurous acid. 

Concerning these patents, William M. Norris says: 

1. Hides or skins are prepared for tanning in the usual way. 

2. They are then subjected to the action of a solution of 
bichromate of potash in the presence of an acid. 



KID OR MOROCCO LEATHERS. 347 

3. The hides or skins are introduced into a second solution, 
which consists of hyposulphite of soda dissolved in water, to 
which an acid is added to liberate the sulphurous acid. 

4. They are then finished in the usual way. 

Some years ago Mr. Schultz sent a circular to the trade in 
which he gives further information, and enters more into details 
about his process, as follows : 

Pickled roans or similar-treated skins, rinse in 70 F. warm 
water, or leave in water over night. 

First Bath. — For every 100 pounds of skins, dissolve 4 pounds 
bichromate of potash in about six to eight times the quantity 
of boiling water, then add 2 pounds muriatic acid, stir well, and 
leave stand about half an hour, then add this liquor to the vat 
containing water sufficient to cover the skins, which must be 
suspended in it. The suspended skins should hang sufficiently 
far apart to allow the liquor an uniform penetration, which 
cannot be accomplished if the skins touch and press each other. 
Leave the skins in this liquor until the yellow color of the 
chrome has thoroughly penetrated, which can be perceived by 
cutting off a small piece from the thickest part of an average 
skin, and if the cut-off part shows an even yellow color, then 
the skins are done ; take out ; let drain, press out adhering 
liquor (perhaps a centrifugal machine will do it), and the skins 
are now ready for the second bath. 

Second Bath. — For every 100 pounds skins dissolve in the 
vat containing the water in which the skins have to be sus- 
pended and sufficient to cover the skins, 10 pounds hyposul- 
phite of soda; stir well until all is dissolved, then add 2^ 
pounds muriatic acid, stir again, and enter at once the skins 
which were done in the first bath, and keep the skins suspended 
in this liquor until the yellow color has disappeared and the 
skins have become whitish all through, which can be perceived 
by cutting off a small piece of the thickest part of the skin. 
Now take out, let drain, press out surplus liquor, and the 
skin has become leather and may now be finished in the ordi- 
nary way. I found it advantageous for suppleing the leather 



348 THE MANUFACTURE OF LEATHER. 

to put in a solution of about 3 or 4 per cent, soap, leave it in 
several hours or over night, or rub a soft soap on both sides 
and let it lie sometime. -Steer skins for sole leather, or any- 
other leather which is suppled by grease, should receive such 
grease soon after coming from second bath and before the 
leather has commenced to dry. 

The advantages of making leather by this process are : It is 
adapted to all kinds of hides or skins, furs or chamois. The 
leather by this process is much denser — tougher — therefore 
more durable than leather made in the ordinary way, by tan- 
bark, sumac, gambier, etc. The leather by this process can be 
boiled in water without impairing its quality ; it remains leather, 
while all other leather made by tannin will be totally spoiled — 
destroyed by boiling. The thinner kinds, as sheep, will not 
shrink by boiling. The boiling test is a characteristic mark of 
this process. Because belts have sometimes to be exposed to 
heat, which is hurtful to tanned leather, beltings made from 
leather by this process promise more durability. The dyer is 
enabled to make brighter colors ; on account of the color of this 
leather being whitish, it taking color with great ease. Sole 
leather now made at the depots of tanbark can be made by this 
process near any city. The freight to and from present tan- 
neries is almost entirely saved. The saving of time and of 
interest on capital, is large, because the tanning of hides and 
skins by this process, as steer-skin for sole leather, takes only 
forty-eight to ninety-six hours according to thickness. Sheep- 
skin skivers may be done in about three hours, sheep-skin roans 
in three to six hours, sheep-skin fleshes, for chamois or gloves, 
in three hours. The materials used for this process are of low 
cost. 

The bichromate, or first bath, if not exhausted, may remain 
for the next lot, only adding thereto a suitable quantity of 
bichromate and acid. For the hyposulphite bath it may ap- 
pear well to use at first only half of the given quantities, and 
after the liquid becomes clear, and the sulphurous acid smell 
is faint, and the skin showing to need more, then more hypo- 



KID OR MOROCCO LEATHERS. 349 

sulphite and acid may be added by pouring this additional 
liquor in at one side of the vat without lifting the skins, only 
motioning the skins in vat. The preparing of the skins, as 
liming, sweating, unhairing, plumping, before they enter the 
tan liquors, must be done also for this process, and this pro- 
cess is distinguishable chiefly by the kind of liquor used against 
the ordinary tanbark process. 

Before considering the chemistry of this process, the char- 
acteristics of the articles used, their properties and reactions 
upon one another, mention should be made of Mr. William 
Zahn, one of the pioneer manufacturers of chrome tanned 
leather in this country. Mr. Zahn secured a patent covering 
his process on June 28, il 



SPECIFICATION OF THE ZAHN PATENT. 

My invention, says Mr. Zahn, relates to an improved process 
of tanning skins for making kid leather, and the process con- 
sists, first, in preparing the skins for tanning by treatment with 
sulphide of sodium or arsenic and unhairing the same, then 
treating it with dog manure and a solution of salt and water. 
After this preparatory treatment the skins are exposed to the 
action of three different solutions, the first solution consisting 
of bichromate of potassium, salt and muriatic acid ; the second 
solution of hyposulphite of soda and sulphuric acid, and the 
third solution of a mixture of neat's foot oil saponified by 
caustic soda and extract of quercitron-bark, or other tannin- 
containing extract. 

For preparing the skins and producing a strong and soft kid 
leather in a much shorter time than heretofore, the skins are 
first treated with sulphide of sodium for about three or four 
days — for seven to eight days when arsenic is used. The skins 
are then unhaired, scraped and placed in dog manure for some 
time. The skins are then cleaned of the dog manure and 
placed in a solution of five pounds of common salt and one 
hundred pounds of water, in which they are allowed to remain 
for about one-half hour. They are then removed and ex- 



3 CO THE MANUFACTURE OF LEATHER. 

posed to the first bath, which consists, for every one hundred 
pounds of skins, of a solution of five pounds of bichromate of 
potassium, two pounds of salt, and two and one-half pounds of 
muriatic acid in five gallons of water. The skins are placed 
with this solution in a tub and rotated by stirrers in the same 
for about thirty minutes, so as to be thoroughly impregnated 
by the solution. The skins are then allowed to remain in the 
solution for about three hours, after which they are again 
rotated for about thirty minutes with the same. Thinner skins 
have to be exposed to the action of the solution for a less 
length of time than thicker skins, which have to remain for a 
greater length of time in the solution, so as to be thoroughly 
impregnated by the same. The skins are then transferred to 
the second bath, which consists, for every hundred pounds of 
skins, of eight pounds of hyposulphite of soda (Na 2 S 2 3 ) and 
one and one-half pounds of sulphuric acid of 6 deg. Baume, 
dissolved in ten gallons of water. The skins are placed with 
the solution in the tub and agitated in the same for about 
half an hour. After an intermission of half an hour they are 
again agitated for half an hour, and then allowed to remain in 
the same from two to ten hours, according to the thickness 
of the skins. They are then washed and placed in the third 
bath, by which the leather is made soft and strong, and which 
consists, for every one hundred pounds of skins, of a mixture 
of saponified neat's-foot oil and two ounces of caustic soda, 
which are dissolved in one gallon of water and heated by steam 
until the neat's-foot oil is properly saponified. Then an ex- 
tract of five pounds of quercitron bark in five gallons of water, 
or any other suitable solution containing tannic acid is added. 
The skins are placed with this solution in the so-called " pin- 
wheel," the last solution softening the skins and imparting the 
final tanning action to the same. The skins are exposed to the 
tannic acid solution for about half an hour, after which the 
leather is removed and dyed in the usual manner. 

For light colors, the dye is given to the leather while it is in 
the pin-wheel, it being finally washed off and allowed to dry, 



KID OR MOROCCO LEATHERS. 35 1 

while for dyeing black it is best to remove the leather to the 
working bench and spread the color over the same. A coating 
of oil is then given to the leather on the grain side, after which 
it is dried at a temperature of from jo° to 8o° Fahrenheit. If 
a gloss is to be imparted to the leather, a coating of some veg- 
etable oil, preferably linseed oil, is finally given, which renders 
the leather water-proof, soft and durable. 

By my improved method of tanning skins, the same can be 
changed into leather in from fourteen to sixteen days, the pro- 
cess producing kid leather of superior quality. 

For the chrome bath Schultz directs for each ioo pounds of 
skins 4 pounds bichromate of potash, 2 pounds muriatic acid ; 
and for the hypo bath for each ioo pounds of skins io pounds 
hyposulphite of soda and 2^ pounds muriatic acid; while 
Zahn prescribes for. the chrome bath, for every ioo pounds of 
skins 5 pounds bichromate of potash, 2 pounds of salt, 2^ 
pounds muriatic acid; and for the hypo bath, for each ioo 
pounds of skins 8 pounds hyposulphite of soda and I ^4 pounds 
sulphuric acid of 6° Baume. The strength of the sulphuric acid 
mentioned is probably a mistake. No doubt 6o° or 65 ° Baume 
was what the inventor meant. 

In order to express the composition of substances, and in 
representing the results of chemical action, more conveniently 
than can be done by writing the names of the elementary con- 
stituents at full length, chemists use a kind of short-hand, or 
symbolic language, which is very simple when once explained. 
Instead of writing the whole name, the first letter, or if the 
names of two or more elements begin with the same letter, the 
first two letters of the name are employed to designate the ele- 
ment; sometimes using the Latin or Greek name. Thus, in- 
stead of hydrogen, we write H ; for oxygen, O ; for nitrogen, 
N, etc. For carbon we write C ; for chlorine, CI ; for chro- 
mium, Cr, etc. For iron we write Fe, from Latin ferrum ; for 
copper, Cu, from cuprum ; for potassium, K, from kalium ; for 
sodium, Na, from natrium. These letters, however, signify 
more than this ; they stand not only for the elements in ques- 



352 THE MANUFACTURE OF LEATHER. 

tion, but they all have certain numbers belonging to them, 
which indicate the proportions by weight in which the several 
elements are found to combine with each other. Thus, H does 
not signify any weight of hydrogen, but always I part by weight. 
O signifies always 16 parts by weight of oxygen, because it has 
been found that the density or weight of a given volume of 
oxygen compared with that of the same volume of hydrogen is 
1 6 — hydrogen, as the lightest body known, being taken as the 
unit; so all the other elements have in the same way been 
compared with hydrogen and certain numbers given them, 
which is their weight. CI (chlorine) is 35.5; K (potassium) 
is 39; Na (sodium) is 23 ; S (sulphur) is 32. Hence, it is 
evident that we may express by symbols not only the qualita- 
tive but also the quantitative composition of chemical sub- 
stances. Thus, water consists of 

Hydrogen 2 X I or H 2 . 

Oxygen 1 6 or O. 

The symbol for water is, therefore, H 2 0. The juxtaposition 
of the letters signifies that the elements are combined together 
in the proportions by weight indicated by the respective letters. 
The figure 2 placed below the letter H shows the combining 
weight of hydrogen ( I ) is to be taken twice. The sum of the 
combining weights, in this case 18, is the combining weight of 
the compound, water. 

In preparing the chrome bath each of the inventors uses a 
certain quantity of bichromate of potash and one-half this 
quantity of muriatic acid. The reactions which occur here are 
K 2 Cr 2 7 (bichromate of potash)+2HCl (muriatic acid)=Cr 2 6 
(chromic acid)+2KCl (chloride of potash)+H 2 (water). 
That is, the muriatic acid breaks up the bichromate and forms 
chromic acid, chloride of potash and water. But why should 
one-half the quantity of acid be used? 

To find the combining weight of bichromate of potash : 



KID OR MOROCCO LEATHERS. 353 

The weight of K is 39, that of K 2 is 78 

The weight of Cr is 52.5, that of Cr 2 is 105 

The weight of O is 16, that of 7 is 112 

K 2 Cr 2 7 (Bichromate of potash) is 295 

The weight of H is 1 

The weight of CI is 35.5 

HC1 (muriatic acid) is 36.5 

2HCI is 73, so when 295 parts of bichromate of potash are 
taken, 73 parts of muriatic acid are required, or when 1 pound 
of bichromate of potash is taken 0.248 pound muriatic acid is 
required — say y^ of a pound. But this is on the supposition 
that the articles are of full strength and chemically pure, which 
is generally far from being the case. Muriatic acid is a colorless 
transparent gas ; it dissolves in water very readily, and in this 
combination is known in the trade. The commercial article is a 
yellowish liquid, the color being due to the presence of impur- 
ities. A strong solution of the gas, which stands about 25 de- 
grees Baume, contains 40 per cent, of muriatic acid. The 
ordinary commercial article stands from 18 degrees to 20 de- 
grees Baume, and contains about 30 per cent, of muriatic acid. 
Now, granting that the bichromate of potash of trade is pure 
and of full strength, 1 pound would require about ^ of a 
pound of muriatic acid to liberate all the chromic acid. 

In the hypo bath Schultz takes 10 pounds hyposulphite of 
soda and 2]/^ pounds muriatic acid, while Zahn uses 8 pounds 
hyposulphite of soda and \ x / 2 pounds sulphuric acid. It is im- 
material which acid is used, as the function of the acid is to 
break up the hyposulphite of soda and liberate the sulphurous 
acid, which is what is required to set the chromic acid in the 
skins. 

The formula is, where muriatic acid is used : 

Na 2 S 2 3 +5H 2 (hyposulphite of soda)-|-2HCl (muriatic acid) 
=S0 2 (sulphurous acidj+S (sulphur) +2NaCl (chloride of 
sodium ) +H 2 (water). 

Thus we have sulphurous acid, which is given off as a gas 
23 



354 THE MANUFACTURE OF LEATHER. 

with its peculiar, characteristic, pungent odor, sulphur which 
separates out as a yellowish white powder, chloride of sodium 
which remains in solution. 

To determine the proper amount of acid to use in connection 
with the hypo : 

The weight of Na is 23, that of Na 2 is 46 

The weight of S is 32, that of S 2 is 64 

The weight of O is 16, that of 3 is 48 

The weight of H 2 is 18, that of 5H 2 is 90 

Na 2 S 2 3 5H 2 (hyposulphite of soda) is 248 

We have previously determined that the combining weight 
of muriatic acid is 36.5. So where 248 parts of hyposulphite 
of soda are taken, 73 parts of muriatic acid are required, or to 
1 pound of hyposulphite of soda 0.3 pounds muriatic acid ; 
but as muriatic acid is only 30 per cent, pure, 1 pound. So 
where 1 pound of bichromate of potash is taken, ^ of a pound 
of muriatic acid should be used, and to each pound of hypo- 
sulphite of soda 1 pound muriatic acid. 

In the same way we can determine the proper relation 
between the bichromate and the hypo : 

Cr 2 O g (chromic acid) + 3S0 2 (sulphurous acid) + 3H 2 (water) = Cr 2 O s 
(chromic oxide) -\- 3H 2 S0 4 (sulphuric acid). 

The weight of Cr is 52.5, that of Cr 2 is 105 

The weight of O is 16, that of 6 is 96 

Cr 2 6 (chromic acid) is 201 

The weight of S is 32 32 

The weight of O is 16, that of 2 32 

S0 2 (sulphurous acid) is 64 

3S0 2 (sulphurous acid) is 192 

Therefore 20 t parts of chromic acid require 192 parts sul- 
phurous acid. 

Now, glancing at first series of formulas it will be seen that 
295 parts of bichromate are necessary to produce 201 parts 
chromic acid ; and from second series formulas it will be seen 
that 248 parts of hyposulphite of soda are required to produce 



KID OR MOROCCO LEATHERS. 355 

64 parts sulphurous acid. But as 192 parts of sulphurous acid 
are necessary, it will require 744 of hyposulphite of soda. So 
when we take 295 parts of bichromate of potash we require 
744 parts of hyposulphite of soda, or when 1 pound of 
bichromate is used, 2.53 pounds, of hyposulphite of soda are re- 
quired — say ly? pounds. 

In this manner we arrive at the theoretical quantities of the 
different ingredients used, but it has been found expedient to 
vary the relative quantities in practical use. 

Both inventors first saturate the skins with chromic acid and 
then reduce this chromic acid to chromic oxide by means of 
sulphurous acid. 

When a solution of bichromate is acted upon by muriatic 
acid, chromic acid and chloride of potash are formed. This 
chloride of potash, although it does not assist at all in the tan- 
ning process, at the same time exerts no injurious influence. 
Skins, when saturated with chromic acid, are in a most sensi- 
tive condition, and should be handled most carefully. The 
length of time they are exposed to the air, the state of the at- 
mosphere, and particularly sunlight, all have a marked effect 
upon them. 

When hyposulphite of soda is acted upon by muriatic acid, 
we have sulphurous acid, sulphur, chloride of sodium ; and the 
sulphurous acid, when acting upon the skins, breaks up, form- 
ing sulphuric acid. So the stock is necessarily subjected to 
the action of all the above named articles, which certainly is 
not at all beneficial, quite the reverse. 

Sulphurous acid itself is a difficult reducing agent to prop- 
erly control. It adheres most tenaciously to the skins, and 
efforts made to remove it are not always successful. To this 
are due many of the troubles which beset the manufacturer who 
undertakes to work this process, because when leather is 
finished without having previously thoroughly removed every 
trace of sulphurous acid, it will harden, crack, show grease 
spots, and be in every way most unsatisfactory. In fact, to 
proceed to manufacture leather according to the directions 



356 THE MANUFACTURE OF LEATHER. 

which these inventors give us, would result in a not very satis- 
factory or salable product. After the skins have been tanned 
in the liquors above described, they should be washed in warm 
water, then in ^ to I per cent, borax solution, and finally in 
water. All chrome goods must be fat liquored (see Chapter 
XV.) and dyed before they become dry, or soaked in some kind 
of a solution to prevent complete drying out, as one contain- 
ing 5 per cent, salt and 5 per cent, glucose. 

PUTTING-OUT MACHINE. 

The work of "putting out" goat and sheep-skins in the pro- 
cess of manufacturing Morocco leather was commonly done by 
hand ; but machines have been invented for this purpose that 
are steadily coming into use. 

The object is to press out the water and tanning liquor, and 
to scrape off the small pieces of flesh or other imperfections 
that adhere to the flesh side of the skin, and to render the grain 
side smooth and otherwise to improve its appearance. 

Fig. 96 shows a perspective view of Vaughn's machine for 
"putting out" and also striking out goat, sheep, calf and kan- 
garoo skins. It is built by the Vaughn Machine Co., Peabody, 
Mass. 

This machine is so well and extensively known and used 
throughout this country and Europe that a description is hardly 
necessary. It is the only machine that will do the work, and 
its excellence is proved by the fact that it now has nearly sup- 
planted all hand work in this branch of the business. Its con- 
struction consisting of two parallel cylinders, revolving in op- 
posite directions, and a vertical table on which the skin is placed 
passing up through them, is sufficient to convince anybody that 
it cannot help doing the work much better than it can be done 
by hand, as the whole skin is worked at once and from the 
back to the belly, taking out all bag and stretch thoroughly, 
leaving the skin fine, dry, even, smooth, and in perfect shape ; 
in fact, perfectly put out in every particular. 

The manufacturers guarantee that this machine will put out, 



KID OR MOROCCO LEATHERS. 



357 




both first and second way, all kinds of chrome-tanned stock, 
Russia calf and all fancy-colored skins, India tanned goat and 
sheep-skins in any finish, sheep-skins either bark, sumac, or 
Dongola tanned, glazed, mat or dull kids of any tannage, kan- 



35 8 THE MANUFACTURE OF LEATHER. 

garoo skins, and in fact anything that is now made by manu- 
facturers of morocco and light leathers of all kinds ; that it will 
entirely take the place of all hand work for this purpose in the 
factory. 

The same machine will either strike out or put out, or both. 

They claim a decided gain in measurement over hand work, 
besides the great saving of labor. Very little space or power 
is required to operate it. Each machine is fitted specially 
with the proper cylinders for doing any particular kind of work 
required, and guaranteed to give perfect satisfaction. The 
machine is very efficient, and it leaves the skins dry, even 
smooth, and in a most desirable condition. 

Necks, butts, and shanks are also put out by it in a better 
manner than it is possible to perform the work by hand. 

Under the present system of chrome tannage every step of 
the finishing process is accomplished by a different person, 
each man having his own specialty. A seasoning mixture is 
applied to the surface after tanning and before coloring. 

Fig. 97 shows a form of seasoning machine which is largely 
used for all kinds of glazed kid. It is the invention of Shute 
and Faulkner, Lynn, Mass., practical morocco manufacturers, 
doing a large glazed kid business and whose seasoning is done 
wholly with this machine, as is also that of nearly all the other 
Lynn manufacturers, who will attest to the efficiency and prac- 
ticability of this machine for the above named work. 

The machine is built by the Vaughn Machine Co., Peabody, 
Mass. 

In construction it consists of a wheel, carrying two sets 
of flexible pads, arranged on opposite sides of the wheel, 
beneath the wheel two circular forms attached to levers, treadle 
rods and treadles to raise and lower them, each form to serve as 
a bed for the set of pads which pass directly over it, and a 
metallic apron or spreader above the wheel to distribute the 
seasoning evenly on one set of pads, together with the table to 
support the skin, and shelf to hold the seasoning tank. 

The mode of operating the machine is, to pass a skin under 



KID OR MOROCCO LEATHERS. 



359 



the wheel, between the pads and circular bed, to start the sea- 
soning running, usually from a slow to a very fast drop is suffi- 
cient, according to the quantity of seasoning required to be 
spread on the skin. By placing the foot on the treadle it 

Fie. 97. 




SEASONING MACHINE. (FAULKNER PATENTS.) 

brings the skin up to and in contact with the revolving pads, 
then by drawing the skin from the left to the right, the left 
hand or spreading set of pads passing over the skin first 
spreads the seasoning, and the right hand set, which remains 
comparatively dry, following after the wet ones, rubs the sea- 
soning thoroughly into the skin. 



360 THE MANUFACTURE OF LEATHER. 

The quantity of work that a- machine will do depends so 
much on the condition of the skins and the seasoning, that no 
definite numbers can be given, but it has been found in almost 
every instance to do from two to three times as many as can be 
done by hand. The quality of work is always as good, and in 
many cases better than previously done by hand, owing to the 
immense amount of rubbing that the machine does, which can 
be better understood by a comparison of the number of strokes 
it makes on the skin, with the number made by hand in the 
same time. 

Allowing a man to make a stroke a second, which would be 
very fast work, the machine carrying twenty pads runs at 
eighty revolutions, making 1,600 strokes per minute against 60 
strokes by hand. 

The machine can be easily adjusted to the pressure re- 
quired, also to make it season heavy either on the sides or 
middle of the skin. 

Owing to its simplicity of operation, and good results in both 
quality and quantity of work done, it is fast being adopted by 
all leading manufacturers of the country, and cannot help being 
universally used by all manufacturers of glazed kid in the near 
future. 

For seasoning use ^ blood, % flaxseed water strained, and 
a few drops of sulphuric acid ; this makes a splendid strong 
seasoning. In some factories they use I pint of milk and I pint 
of water. 

The skins are then thrown into the coloring drum and 
thrashed about in the coloring liquid for an hour. The plaiter 
next takes it in hand, folds it down the back, face out, and runs 
lightly over it with a tool known as a " slicker," causing the 
inner sides to closely adhere. Then he rubs in a scour with a 
hard brush, and the skin is turned over to the boxman. This 
latter dips it into a box filled with a black liquid, and turns and 
shifts it for some fifteen minutes. Then it is run through a 
"striking-out" machine shown in Fig. 96, which removes all 
superfluous moisture. The skins are then packed in saw dust, 



KID OR MOROCCO LEATHERS. 



361 



staked and shaved down on the emery wheel and then the skin 
is glazed by machines, seasoned a second time with milk and 
water and reglazed, after which it is hung in a steam-heated 
room to dry, and this, save for light oiling, completes the pro- 
cess. 

In Figs. 98 to 105 we show the plans of the kid factory 
of F. Blumenthal & Co., Wilmington, Del. This is one of the 
largest establishments of its kind in the United States using the 
chrome process and is at the present time being greatly en- 
larged. 



Fig. 98. 



UI „ A c N °lDDDDDDDD 
■WSBSP 1™ Pure Tubs 

EN61HE 

d DDDDDDD 



-33ft 



Beam House 

Machine 

Shop 



Fig. 99. 



35<fip 
Engine 



o □ 



DD DDD DD 

Wash Reels 



DDDDDDD tS„ a ri g HI ° 6 J? N0 

Pure Tubs Staking machines 

DDD DD 11 a □ odd 



IBOILERSI" 



O s teaming 

PURE DDD 



FI-RST FLOCTR. 
167ft- - 



:de 



1 



TJE 

QCE 
□DC 
DDL 
DDE 
DLT 

ax 

L.MES QD [; 

BE 

LXL 




110 ft 



The plans show the number of machines in each room, but 
do not show the fifth and sixth floors, which are mainly de- 
voted to steam drying. There are, however, above the perch- 
ing room on the fourth floor, two large logwood tanks, and in 



362 



THE MANUFACTURE OF LEATHER. 



the opposite wing, above the general storeroom, a sawdust 
room. 

The capacity of the plant is 1,500 dozens of skins daily. The 
machinery is of the latest and best. There are 33 Vaughn 
machines, 186 Bowers glazing machines, 70 Hysore glazers, 
20 color boxes, 12 pleating tables, 6 blue backing and fat 
liquoring drums, 14 tanning drums, 44 hypo, reels, 28 Weber 



Fig. 100. 



DDDDD DDDO D 

VaughnStriking-Out Machines 
Tanking Drums 

D DDDDOD 

, =J DDDDOnDD 

Hypo Reels 
DOQaDDDQQQQ 



anna ! ddd 

a a a o Color J ana 
a a a a Room "^ ana 

dOOD = D DD 

a a a a 2 ddd 

Color Tables a. 




SECOAID FLOOn 



Fig. ioi. 




stakers, 50 knee stakers and 12 Slocomb perching machines. 
These perching machines take the place of hand work, as 
they are far more efficient and speedy. About 1,000 hands 
are usually employed ; 200 girls do the seasoning, glazing and 
measuring. The product is glazed kid, black and in colors. 

This firm was among the first to adopt the chrome process. 
They bought the Schultz patent, and sold it to the Patent Tan- 



KID OR MOROCCO LEATHERS. 
Fig. 102. Fig. 103. 



363 




DD D D D 

Slocomb Perching machines 

□ DD D D D 



OlLINS 
OFF 

Room 



Assorting 
Room 




8=1! 



Sawyer Q 
measuring,-, 
Machines 



Bowers Glazing 

imiiiiiiiuiimiHimmii 
immiiimiiiiiMHitimim 

Machines 



THIHTJ FLOOR. 



FlG. IO4. 



Fig. 105. 












Drug 




Room 


seasoning 
Room 






1. . p*" 




j Seasoning Room 


U . __ 



POUT^TH PI_00"R- 



nage Company, of Philadelphia, Pa., reserving to themselves 
the right to use it. They import all the skins they tan, and 
have the advantage of a close European selection. 



364 THE MANUFACTURE OF LEATHER. 

INDIA TANNED GOAT. 

The finishing of India tanned goat skins is an important 
branch of manufacture in Peabody, Mass., and in some other 
parts of the country. 

In good times several thousand dozens of these skins are 
finished in Peabody every week. The amount of goatskins 
imported from India greatly outnumbers that of the sheep, and 
they fill a place in the manufacture of shoes entirely distinct 
and independent. All the Morocco leather that is produced in 
the United States from skins in the hair is made by the chrome 
or oxide process, which renders it soft, springy and elastic, and 
entirely unfit for pebble grain work. Here is where the India 
goat comes in. Being tanned in the slow, natural way, it has a 
firmness and body entirely suitable for graining and pebbling. 
It also makes a cheap kid a pretty fair color, and a dull 
Dongola for men's shoes. All these skins undergo cleansing 
and retanning processes, and while furnishing leather for 
ordinary grades of shoes, do not conflict with the chrome 
leather, except on a few lines. 

There is some Morocco leather still produced in the United 
States by the old method of sumac tanning. 

SUMAC TANNED SKINS. 

If the skins have been tanned with sumac they are next 
"struck out" on mahogany tables, which are so shaped as to 
slant from the workman at an angle of about 45 . 

A steel "slicker" is used for this operation, and an average 
workman will "strike out" about 200 skins in ten hours. 

The object of this operation is to increase the size of the 
skins, remove the adhering "fleshings," tanning liquors, and 
water, and render the skins smooth and even, and this is ac- 
complished in many tanneries by the employment of machinery. 

The skins after being " struck out " are hung- up in the dry- 
ing lofts and dried by the atmosphere ; the time required for 
this depending upon the condition of the weather. 

Fig. 106 shows the drying loft in a Morocco factory, the skins 



KID OR MOROCCO LEATHERS. 



365 




366 THE MANUFACTURE OF LEATHER. 

being hung on hooks which are shown on the racks placed at 
a convenient height from the floor. When sufficiently dry the 
skins are removed from the hooks and carried -to a room on 
the same floor as the loft, and there assorted according to the 
kind of leather into which they are to be finished. This im- 
portant point having been decided upon, the skins are removed 
to the cellar and wetted down in soap-water, and while wet the 
skins are carried to a currier's beam and shaved with a currier's 
knife on the flesh side, so as to make them of a uniform thick- 
ness, and also for the purpose of having them receive a better 
finish. 

From this point all the skins pass to the finishing-room, and 
as each kind of Morocco leather requires a different treatment, 
we will now describe each separate mode of finishing the various 
kinds. 

FINISHING IMITATION OF FRENCH KID. 

This class of leather has taken a high rank in our country, 
and it is now generally conceded to be much superior to the 
genuine French kid for wear. 

The skins, after being treated as above described, are carried 
to the coloring table and colored on the grain side, with an iron 
and nutgall-black having a logwood body, which gives a clear 
and bright black, and after being blacked the skins are hung 
up in the loft. The skins, after the first blacking has dried, 
next pass into the finishing-room, and the second application of 
black is made, which is similar to the first, with the exception 
of the nutgalls, which are omitted ; bichromate of potash is 
sometimes used in this black, but in small quantities. After 
this second application of color, the skins are hung upon racks 
in the finishing-room, and left until the color sets or dries, the 
blackened side being turned inward, as shown in Fig. 107, 
which shows a perspective view of the blacking tables and an 
interior perspective view of the finishing-room. 

After being removed from the hooks they are next moistened 
with a solution of milk and water, and are then ready to be 



KID OR MOROCCO LEATHERS. 



367 




368 THE MANUFACTURE OF LEATHER. 

glazed, which operation is performed by machines of various 
constructions, and which have been heretofore explained in 
Chapter XIX. 

The skins are next softened by hand with a board and 
scraper, or, as it is termed, a "softening slicker." 

They are then oiled with the best sperm oil, which is applied 
with a rolled-up flannel cloth. 

The skins are glazed two or three times as the case requires, 
the oil is applied twice, and after the last application the imita- 
tion French kid is ready for market. 

In selecting skins for the production of this class of leather, 
their weight is regulated by the demands of the trade, at times 
being light, and at others heavy. The skins are also selected 
for their cutting qualities, those which are free from blemishes 
or breaks being, of course, more valuable than those that are 
scratched. 

FINISHING BRUSHED KID. 

The finishers take the South American goat-skins from the 
shaving-beams and " put them out," and each man will put out 
and black five dozen per day, and after being thus treated they 
are hung in the loft and dried by the atmosphere. 

The skins are blacked and seasoned with the same prepara- 
tion of bullock's blood, iron, and vinegar black, which is applied 
with a piece of flannel cloth made into a roll. They are then 
wet over with gum-water and brushed with a very soft brush, 
called a "kid-brush." After being hung in the loft and dried, 
the skins are next " back-boarded," then glassed, and next 
rolled by a machine having a steel roller. 

The finisher takes the skins from the rolling machine and 
scrapes them with a steel slicker in order to loosen up the flesh, 
after which the grain side is oiled with the best sperm oil, which 
is applied by means of a roll of flannel cloth. The brushed kid 
is now completed and ready for market. 

FINISHING STRAIGHT- GRAINED GOAT. 

The first step after shaving in finishing this variety of 



KID OR MOROCCO LEATHERS. 369 

Morocco is the " putting-out," which is performed by working 
over both sides of the skin with a steel slicker. This portion 
of the work is usually accomplished by machinery. When 
done by hand about five dozen large skins or nine dozen small 
ones are put out by a skillful workman in one day. The skins 
thus treated in the morning are placed in the loft, and in the 
afternoon they are " put out the second way," which consists 
in smoothing the grain side. They are drawn out and the 
•stretch removed in the first operation. 

When the skins are placed in the loft they are spread out 
separately on the floor, as shown in Fig. 108, and are not 
allowed to become too dry, and in the afternoon when they are 
"set out the second time," no water issues from them. After 
being set out the second time they are returned to the loft and 
placed on trestles, which are about two feet six inches high, and 
they remain in this loft until dry, the period of course depend- 
ing upon the state of the weather. 

The day's work of each man is kept separate from that of 
the others, and each workman hangs up his own day's work of 
skins, one on each hook, and so placed that none of them touch 
each other. 

When dry the skins are packed in piles, those that are in- 
tended to be stained on the flesh side being separated from 
those that are to be pebbled. 

They are next carried to the finishing-room and the rough 
part of the grained side is smoothed off with a piece of fine 
emery paper, rolled so as to expose the length of the paper to 
the skin. 

This portion of the work is sometimes accomplished by 
machinery; a revolving emery stone, such as is used in the 
manufacture of kid gloves, being employed, the dust being 
blown from the stone by a suitable fan. 

The skins are next seasoned, which is accomplished by coat- 
ing them with a preparation of bullock's blood, logwood boiled, 
cow's milk, water, and a small quantity of vinegar black, made 
by treating iron with vinegar, one gill of the latter preparation 
24 



37° 



THE MANUFACTURE OF LEATHER. 




= a 



= a 



■ & 



KID OR MOROCCO LEATHERS. 



371 



being used for a bucketful of " seasoning," which quantity 
will season above five dozen straight-grained goat-skins. After 
the seasoning has dried they are regularly blacked and hung up 
in the finishing-room, as shown in Fig. 100, and after remain- 
ing on the hooks for about one and one-half-hours, or until the 
dampness leaves the skins, they are rolled by machinery. After 
being rolled the skins are again hung up in the finishing-room 
and remain over night, and in the morning they are glazed on 
a machine having a glass roller. Fig. 109 shows a rolling and 
glazing-room in a morocco factory. 

The number of skins rolled or glazed is from 30 to 50 dozen 
per day for each machine, depending upon the speed at 
which the machine is driven, and also upon the size of the 
skins and quality of the work. Some are glazed lighter than 
others, in order to give a medium gloss, but when a high gloss 
is desired, extra pressure is applied. 

After the skins are glazed they are wetted in cold water by 
passing them through a large tub holding about 50 gallons, and 
the workman in accomplishing this takes two of them and 
places them grain to grain, and grasping hold of the butt of the 
skins draws them slowly towards him. 

They are next grained, which may be performed either by 
hand or machinery ; if done by hand, a graining board similar 
to that shown in Fig. 1 10 is employed. 

Fig. 109. 




These graining boards are made with a cork face, and in 
using them the arm passes through the strap and the hands 
grasp the handle. 



372 



THE MANUFACTURE OF LEATHER. 







KID OR MOROCCO LEATHERS. 373 

The object in using this tool is to raise the grain and to make 
the straight-grained goat-skins more durable, and also has the 
effect of rendering them more pliable as well as tougher. 

The skins are again hung in the loft, usually above the finish- 
ing-room, and dried by the atmosphere, which requires from 
24 to 48 hours, according to the state of the weather. After 
this drying they are again grained, which has the tendency to 
raise the figure and further mellow them. All the graining 
is done on the grain side ; but after the second graining they 
are " back- boarded " on the flesh side, which has a tendency 
to make the figure more uniform as well as to still further soften 
the skins. 

An application of best sperm oil to the grain side of the 
skins completes the finishing of straight-grained goat, and as 
the oil is immediately absorbed by the pores, the skins are at 
once ready for market. 

From the time that they enter the finishing shop to the time 
that the straight-grained goat is ready for market, the period is 
about seven to ten days, being shortest in good drying weather 
and longest when the condition of the atmosphere is not favor- 
able. There is also a grade of Morocco leather known as 
" caracal," which is straight-grained calf, and its peculiarities 
are pliability, toughness, gloss, and superior finish. This 
leather has a fancy finish, and its introduction into the trade 
has been but to a limited extent. 

FINISHING PEBBLE-GRAIN GOAT. 

The difference in finishing pebble-grain goat fromstraight- 
grained is that the first named is "cut" four ways in 
the process of hand-finishing, in the softening, and in the 
"springing up;" but in "back-boarding" it is cut two ways 
only. The skins are pebbled on the same machine, but not 
with the same roller that is used for straight graining. 

FINISHING OIL GOAT. 

In finishing "oil goat," after the skins have been "put out 



374 THE MANUFACTURE OF LEATHER. 

the second way" and blacked, they are then stuffed with 
dubbing on the flesh side. The dubbing is composed of one- 
half oil and one-half tallow when used during the winter time ; 
but in the summer more tallow than oil is used. They are 
then hung up to dry, after which they are grained three ways 
and then treated to a coat of dubbing on the grain side, after 
which they are flattened down on the grain side with a dull 
slicker, and after being treated with a coat of fine sperm oil 
which completes the finishing, the oil goat-skins are then 
measured and marked ready for the trade. 

This class of Morocco leather is more water-proof than the 
other grades of sumac-tanned skins, and is used in a small way 
for ladies' heavy wear, and sometimes boys' boots are made 
from it. 

The heaviest skins are used for this kind of leather, and the 
kinds commonly employed are Tampico, Capes, and Patnas. 

COLORING. 

William M. Norris, of Princeton, N. J., gives the following 
information about coloring: 

" At the present time, when the greatest economies are essen- 
tial, it would doubtless occur to some manufacturers of glazed 
kid that a saving might be effected if they themselves made 
their own " Black," " Sig," "Seasoning," " Stains," &c. Even 
if successful in producing good articles, which is very doubtful, 
the saving is infinitesimal and the economy a most costly one. 
Take "Black" for example ; a barrel of "Norris Black" will 
color about 600 dozen skins and costs about $7.50. Say these 
skins measure 50 feet to the dozen, we will then have 30,000 
feet of skins, and the black therefor will cost -^ of a cent a 
foot. Provided the black made by the leather manufacturer 
himself costs nothing, the saving is hardly visible ; the differ- 
ence in color will, however, be quite apparent. 

" It is in fact, determined by long experience, that in all manu- 
facturing operations the fewer the articles made, and the more 
attention is concentrated on these few, the greater perfection 



KID OR MOROCCO LEATHERS. 375 

will be attained. A specialist in the manufacture of coloring- 
materials for leather who thoroughly understands the proper- 
ties and relations of the raw materials employed, and the best 
methods of combining them, will produce far better and more 
economical products than the individual leather manufacturer." 
Mr. Norris makes a black which is a great favorite for chrome 
tanned leather. 

DONGOLA CALF. 

Make packs of convenient number according to size of soaks 
and limes, 200 or 250 skins of 9 to 12 lbs. or 7 to 9 lbs. or more 
of small stock. Soak thoroughly and break well, either by hand 
or machine. Trim and re-soak if necessary, before going to 
limes. As red arsenic has a very softening effect in liming 
skins it is generally used on this class of work in connection with 
lime. Makeup limes in proportion of 85 parts lime and 15 
parts arsenic to 400 to 500 gallons water. 

The first lime should be weak or four per cent. Stock should 
be hauled daily and strengthened a little, keeping the above 
proportion of lime and arsenic. Lime eight or ten days. 
When hair slips freely, unhair by machine or hand, carefully. 
Wash in hide mill or paddle vat until stock is fairly clean of 
lime. Flesh on machine ; fine-hair grain on beam and shave 
heads down some. Wash again and then bate fairly low. Some 
tanners use solid bate for this work ; others, a liquid bate. 
Any of the known bates are good. 

After bating, work well on flesh, and slate the grain. Then 
rinse and bran-drench in mill for 45 minutes. After which, 
drain and put in tan. Make up liquor in same way as for goat 
tannage, holding calf in tan 48 hours longer than on goat. 
After eight days in tan, haul and drain well over night and oil 
in mill. To every 150 skins use four gallons (half cod and half 
neatsfoot oil). Run one hour in oil, then remove from mill and 
put in loft to dry. 

When dry, pack down five or six days, then wet back in mill 
to shave, using tan liquor to dampen stock, and don't get it too 



376 THE MANUFACTURE OF LEATHER. 

wet. After shaving, re-tan in mill four or five hours, in four or 
five per cent, strength of liquor. Then put on hooks to dry. 
When dry, wet down in mill to color. 

To every five dozen skins use three pails water and six 
gallons fat liquor. If a good yellow flesh is desired, dissolve 
four ounces auramine in boiling water and add it to fat liquor. 
Run stock 45 minutes in fat liquor, after which color and strike 
out on grain and oil off with half cod and half neatsfoot oil. 

After oiling put in hot room to dry. When dry lay in dust 
to dampen for staking. Stake well on machine, flesh up. Air 
off and pad grain, then put in perch and arm- stake flesh and 
slate grain. Iron and trim, and measure. Then oil off, and 
pack down in oil over night black to black. The next day 
wipe off grain with flannel, and stock is finished, and may be 
sorted and dozened to ship away. 

THE OLD PROCESSES OF CONVERTING GOAT-SKINS INTO " DONGOLA " AND 
OTHER FINE LEATHERS. 

It is the purport of this section to treat, not of the more 
modern tannages, but of the earlier brands that were for a 
number of years, and very justly, regarded as standard — we 
refer to the " Dongola " and preceding tannages. 

The different processes through which goat-skins pass in 
their conversion into Dongola are : Soaking, milling, liming,, 
unhairing, fleshing, washing, bating, slating, bran drenching, 
tanning, striking out, drying, assorting for finishing, wetting, 
shaving, dyeing, glazing and assorting for weight and grade. 

The skins come to the factories in bales — the bales contain- 
ing from ioo to 600 skins each — and are placed in the storage 
room. They are then in a dry state. The first treatment to 
which they are subjected is that of " soaking," which consists 
of placing the skins in vats filled with cold, clear water. Here 
they remain for from 24 to 48 hours, according to the weight 
or texture of the skins. Those possessing a hard fibre will re- 
quire a longer time to become thoroughly softened than those 
of a softer texture. 



KID OR MOROCCO LEATHERS. ^J 

When thoroughly soaked they are taken out and placed in 
the " mill." This is a contrivance which consists of one or two 
large stones revolving vertically on a wooden pit. The stones 
are usually immense granite rollers, about lour feet in diameter 
and from eight to ten inches thick. The pit around which the 
perpendicular stone revolves is about two feet deep. After 
" milling" they are washed until they are thoroughly soft and 
pliable — in fact, in much the same condition as when they are 
taken off the backs of the animals. The skins while milling are 
placed under the roller by a workman, who occasionally turns 
them from side to side, and brings them effectually under the 
operations of the revolving granite block. Of course there are 
other means of reducing skins to the proper state now in use. 

The next process is that of " liming." The skins are per- 
mitted to remain in the limes usually from twelve to fifteen 
days, according, as in the case of other processes, to the texture 
of the skins. The object of the "liming" is to thoroughly 
loosen the hair on the skin, so that it may be afterwards rapidly 
and completely removed. 

We now follow the skins to the unhairing room, where they 
are placed on unhairing beams and depilated and fleshed by 
workmen who use for the process long, rounded knives pecul- 
iarly shaped for the purpoe. All the processes through which 
the skins have up to this stage passed prepare them, by soften- 
ing, removing all impediments and opening the pores, to per- 
mit the ready entrance of the tanning ingredients. The skilled 
tanner will be ever on the alert in his intelligent watchfulness 
through all these preparatory stages, and will exercise his dis- 
cretion as to duration of time, etc., according to the heft of the 
raw stock, the temperature of the weather and the condition of 
the water. 

From the unhairing room the skins pass to the " wash-mill," 
where they receive a thorough washing, removing all adhering 
lime, and preparing them for subsequent treatment. 

The next process to which they are treated is "bating." 
The bate is usually composed of dog munure, dissolved in 



378 THE MANUFACTURE OF LEATHER. 

slightly heated water. This process is now usually designated 
u puring." The skins are left in the bate for about ten hours. 

They are now ready, on removal from the bate, for the slat- 
ing room. Here is completed whatever may remain unfinished 
in the unhairing room by removing every particle of hair that 
may still adhere to the skin. The tool used in this process is 
called a "slater," which in a large degree resembles a "slicker." 

The skins are next subjected to the bran-drench. The drench 
is composed of bran and water. It is slightly heated. 

In the old sumach tannage the skins were next sewed in bags 
and filled with sumach liquor, grain side out. They were piled 
up in a heap in a vat filled also with sumach liquor. In the 
course of one day these skins were rilled and emptied five differ- 
ent times, in order that they might be thoroughly and evenly 
tanned. After this they were transferred to the " striking out" 
room. The "striking out" was performed on mahogany 
tables, slanting downward from the operator at an angle of 
about 45 degrees. For this purpose the " slicker," referred to 
in a preceding operation, was used. In this process the size of 
the skin is somewhat enlarged, and any adhering " fleshing," 
tannin or water, completely removed. The skins during this 
operation became smooth and even, and the work of beautifica- 
tion — if the term be allowable — commenced. 

After being "struck out" the skins were dyed or "blacked," 
usually on a table, the present method of dyeing, of course, not 
being used. 

We next find the skins in the " drying room," where they were 
suspended from hooks in a row along the ceiling. The time 
used for drying was regulated largely by the condition of the 
weather. 

When dry they were assorted for particular finishes, each 
skin being set apart for the finish to which it was best suited. 
After being finished they were again assorted for quality and 
weight, when they were ready for the inspection of buyers. 

Thus it will be seen how very varied and critical were the 
processes through which a goat-skin had to pass during its 
conversion. 



CHAPTER XXIV. 

OAK TANNED SOLE LEATHER — UNSCOURED AND SCOURED 
LEATHER — CUT SOLES. 

THE hides used are the packer hides from the packing 
houses in Chicago, Kansas City, Sioux City, St Louis, Omaha, 
Los Angeles and other points. Country hides and South 
American hides are also employed. 

Texas hides are usually branded and are made mostly into 
unscoured. Those which are unbranded and those having 
only a few brands not very marked are used for scoured 
leather. 

South American hides make a very clear grain scoured 
leather, which is used by manufacturers of best men's shoes. 

The hides are placed in the " soaks," in which they remain 
about three days, the period depending upon their condition 
and upon the temperature of the water in the " soaks." Warm 
water requires proportionately less time than cold water. Some 
tanners claim that warm water will soak hides more efficiently, 
and that the filth etc., can be better removed, or the hide better 
cleansed for the " limes," which is very important. It is said 
that the loss of "hide substance " is also less, because less time 
is required for soaking. 

The water in the "soaks" is changed with each pack of hides. 
To-day, careful tanners withdraw the packs after the first 
day's soaking, run off the dirty water, and replenish with fresh. 
The day of putrid soaks is past. Tanners are saving money 
by keeping their soaks clean and not leaving the hides in 
rotten water. It is a small point, but worth remembering. 

The hides may be fleshed at this stage — called " green 
fleshing," or they go into the " limes " and remain for about 

(379) 



380 THE MANUFACTURE OF LEATHER. 

five days or more and are then unhaired and fleshed, as de- 
sired. 

While in the "limes" the hides are changed each day by 
means of a power reel into stronger lime, and when the hair is 
loosened they are unhaired and afterwards fleshed, and then 
thrown into a vat of clear water and left to remain over night. 

In the morning the hides are removed from the clear water 
and " grained," which process consists in scraping the hides on 
the grain side in order to cleanse them more thoroughly from 
the lime remaining in the pores. 

After being " grained " the hides are again placed in clear 
water, where they remain for three or four hours, which com- 
pletes the beam-house work. 

In some tanneries the unhairing and fleshing is done entirely 
by machinery ; the tanners claiming that the cost of the beam 
house work is only about one third as much when done in this 
way compared to hand labor. Unhairing and fleshing machines 
are shown in Chapter VIII. 

The hides after being unhaired and fleshed by machinery are 
usually bated over night in a bate made by adding about one 
gallon of molasses, or more, to the vat of water. 

Some tanners still flesh and unhair by hand, because the 
machines they tried years ago for these purposes were crude 
and unsatisfactory. Some tanners forget that the modern 
machines are successful, and decidedly economical to use. 
Small tanners may not do enough business to encourage their 
buying beam-house machinery ; but, no matter how large or 
small their place may be, before abandoning all hope of using 
machines let the tanner ask the advice of clever and courteous 
machinery men, who may be able to give some valuable informa- 
tion. Some tanners can unhair by machine all right, but find it 
better to flesh by hand, as they get better sole-leather in this way. 

The sole-leather tanners that we know do not leave the hides 
in lime for more than two or three days. But during this time 
they are handled several times, and the limes kept plunged up. 
The scheme of giving limed hides a warm bath, say 100 to 1 10 



OAK TANNED SOLE LEATHER. 38 1 

degrees, during the night previous to unhairing, seems to work 
pretty well. The hair, after the hides have been pushed some- 
what quickly through the limes and warm water, may come off 
hard on the beam, but this is safer for the tanner than when the 
lime has so dissolved the hide matter after prolonged liming 
that the hair slips off almost by itself. This is all very nice for 
the beamsters, particularly when they are on piece work ; but we 
would prefer giving the men a fair day's pay, so that, even if 
the hair comes off hard and slow, they would not be justified 
in complaining. 

Some tanners are too economical in working the grain, after 
they unhair. Whether machines or hand are used, clean, bright 
leather cannot be obtained unless the grain is carefully and 
thoroughly scudded. There are establishments where hides 
for sole leather are put through a mild bate before being fine- 
haired and worked on the grain. It is claimed that the bating 
by its assistance in expelling lime from the fibre tends to make 
softer and smoother leather. 

Union leather is liable to be cloudy and dirty on the grain 
on account of careless beam-work. Bad salt is also an enemy 
of clean grain. Hide dealers as a rule are willing to accommo- 
date their customers, and it is generally agreed by well-posted 
men that hides cured by Syracuse coarse salt are not so liable 
to have dirty grain as when fine salt or harsh mined salt is 
used. Tanners should ask their hide men to use only the best, 
cleanest and mildest salt. Salt-stained leather is a nuisance 
and an expensive eye-sore, and might be avoided if the proper 
salt were used in curing. Borax is the best agent for preserv- 
ing hides. One pound of borax will go as far as five pounds 
of salt. When borax is used, there are no stains of any kind. 

When sweats are employed it is often good policy to give 
the man in charge of them extra wages of a dollar or two each 
week. This small premium will be a great inducement to him 
to attend zealously to his work. There will be times at dead 
of night when he will have to enter the pits and unhook the 
Tiides, so as to stop the decomposition. In putting sweated 



382 THE MANUFACTURE OF LEATHER. 

hides through the hide-mill, there should be no hurry. While 
there is no need to move the tender stock about too much, the 
work should be well done. In this connection we would urge 
that after soaking dry hides they ought to be specially well 
milled, so as to prevent any hard spots remaining. 

It should be the duty of every tanner to keep a ledger ac- 
count of each lot of hides put through the tannery. He ought 
to isolate each important lot of hides received from each dealer. 
These should be marked with a letter or number and carefully 
followed through the tannery right to the weighing-out scale in 
the leather lofts. It could then be easily discovered which 
dealer it was more profitable to buy from. These suggestions 
may cause careful tanners to smile, but they would be surprised 
if they knew how many tanners there are who take chances on 
what they are doing, trusting to luck to come out all right. 

The hides are next suspended in "rockers," which operation 
is the first stage of the tanning proces, its object being the re- 
moval of the lime still remaining in the grain, the swelling of 
the hide and setting of the color. The hides are rocked from 
two to three times per day. They remain in the " rockers " 
from seven to ten days, depending upon the number of "rock- 
ers " and hides worked per day. 

The hides are now taken out of the "rockers" and rehung 
on sticks in the " handlers," where they remain for ten to four- 
teen days, depending, as before, upon the number of vats and 
hides worked per day. 

In some tanneries the hides remain undisturbed on the sticks 
in the same liquor for the required period ; while in others the 
liquor is changed regularly. Again, in some tanneries the 
hides are handled from one vat into another, that is, the hides 
are moved forward to meet the stronger liquor. 

It should be noted that the quality of leather is made in the 
" rockers" and " handlers," that is, the color, plumpness, etc. 

The liquors supplied to the "rockers" must be mellow and 
not strong. The strength of the liquors must be regulated by 
the number of pits used, so that the green hides should have 



OAK TANNED SOLE LEATHER. 383 

sufficient acid in the pit to purge it of lime and properly start 
the plumping. 

The liquor going on the hides in the "handlers" is consid- 
erably stronger, judgment being used as to the strength, which 
is governed by the extent to which the tanning has progressed 
in the " rockers." 

After "having been in the "handlers" the required time, the 
hides are placed upon a truck and conveyed to the yard 
proper, or "lay-away" yard, where the tanning process is 
completed. The " lay- aw ay vats" are of different sizes in dif- 
ferent tanneries ; the common size being nine feet long, seven 
feet wide and six feet deep ; but those in the yard of The Amer- 
ican Oak Leather Company, at Cincinnati, Ohio, are eight 
feet deep. In these vats the hides are placed one by one, spread 
out flat, and a thin layer of dry ground bark is sprinkled over 
each hide, in order that the liquor may circulate uniformly. 
This bark should not be ground too finely, or it will pack so 
tightly as to prevent the circulation of the liquor which would 
result in imperfectly-tanned leather. 

After the hides have " laid-away " for a sufficient length of 
time to extract the tannin partially out of the " liquor," they 
are taken out and the liquor run off into a receiver through 
wooden pipes and pumped by steam power back to the leaches, 
where it passes through the bark and is re-strengthened and 
then run in new liquor into the tan vats, and the hides are then 
put back as before. 

Each pack is usually " laid-away," that is, given new liquor 
from four to five times, the light hides are "laid-away" four 
times and the heavy hides five times, the whole operation in the 
"lay-aways" extending over a period of nearly four months 
for light leather and four months and a half for heavy leather. 

The following schedule is from one of the largest and most 
successful tanneries in the country, and it will give an idea of 
the time and strength of liquor employed in each layer: 



384 



THE MANUFACTURE OF LEATHER. 



Heavy Hides. 



Layer. 



ist 
2d 
3d 
4th 

5A 



Length 
of time. 



14 days. 
20 " 
25 " 

3° " 

50 " 

139 days. 



Strength 
of liquor. 



3° deg. 
28 " 
30 " 
36 '< 
45 " 



Light Hides. 



Layer. 



ist. 
2d, 
3d. 

4th 



Length 
of time. 



14 days. 
20 " 
30 " 

50 " 

114 days. 



Strength 
of liquor. 



30 deg. 
30 " 
34 " 
45 " 



Hides after coming from the " handlers" go into first layer. 
The liquor used for this layer is the liquor taken from a tanned 
pack, and is fifty days or more old and never very sour. This 
liquor is strengthened with extract to about 30 degrees barko- 
meter, and heavy hides are laid away for fourteen days with 
bark as has been described. The pack of hides is then drawn 
and then laid-away again in a fresh sweet bark liquor which 
has been strengthened with extract to about 28 degrees, where 
they remain about twenty days. Pack is again drawn and put 
with the third layer, which is a fresh sweet bark liquor streng- 
thened with extract to about 30 degrees barkometer, where 
they remain for about twenty-five days. Pack is again drawn 
and put into the fourth layer, which is fresh sweet bark liquor 
strengthened with extract to about 36 degrees barkometer, and 
where they remain for thirty days. Then the pack is again 
drawn and placed in the fifth layer, which is fresh sweet bark 
liquor strengthened with extract to 45 degrees barkometer, 
where they remain for fifty days. 

The light hides are laid away only four times, the length of 
the layers and strength of the liquors being indicated in the 
schedule. The strength of the liquors should be determined 
by chemical analysis, which shows that the amount of tanning 
substance per degree barkometer in sweet fresh liquors in- 



OAK TANNED SOLE LEATHER. 385 

creases directly as the degree of barkometer. As an example : 
A ten degree chestnut oak bark liquor contains about 1.25 per 
cent, of tanning substance, a twenty degree liquor contains 
about 2.50 per cent, of tanning substance, and so on. 

The hides after being tanned are taken out of the vat and 
split into sides. The sides are now rinsed in the liquor in 
which the tanning has been finished and are then piled to drain, 
say over night. The sides are then oiled on the grain side with 
cod oil, fish oil, or a mixture of mineral and fish oils. The oil 
is applied with a sheep-skin swab or a cloth swab. 

The sides are now hung up on sticks, which are partially 
rounded upon the edge that comes in contact with the leather, 
in the drying room to dry. The sticks upon which the sides are 
suspended in the drying loft, are 2 in.x2 in. and 8 ft. long; two 
sides are suspended upon each stick about one foot apart, and a 
passage-way 6 feet wide is maintained in the centre of the loft, 
and on each side of this passage-way two rows of sticks for 
holding the sides are placed. 

The drying room is heated with a suitable steam pipe 
system so arranged as to distribute the heat gently and uni- 
formly, and fans so placed as to draw off the moisture from the 
drying room as fast as it is given off by the leather. 

In drying sole leather it is very desirable that too much light 
should not be allowed to enter the loft, as it is injurious to the 
color. 

The temperature of the drying loft is kept at yo° to 8o° F., 
care being observed not to get the temperature too high. In 
the summer time the loft is kept closed and the room darkened, 
some tanners even going to the expense of having double 
shutters on the windows. 

With an intelligently constructed drying-loft, sole leather wet 
from the vats can be dried in forty-eight hours, ready for the 
roller, but some tanners prefer to dry it for a longer time. When 
the sides are thoroughly dry they are taken to the rolling room, 
which is well lighted, and dipped in clear cold water, and when 
the leather is hard it is dipped in a warm water bath. 
25 



386 THE MANUFACTURE OF LEATHER. 

The sides are now piled and covered and allowed to " sammy" 
or become of a uniform temper. They are then rolled and 
hung up in the loft to dry, and when dry are ready to be sorted 
for market. 

The above description is for leather with a bloom. 

The question is often asked us : " How much or what per 
cent, of rough leather can be obtained from the various grades 
of hides." Our answer is as follows : 

Oak. Hemlock. 

Green Salted Hides about 50 per cent. 55 to 80 per cent. 

Dry " " 1 12 to 122 " 

Plint " 100 to 175 " 

For scoured leather the hides are split and rinsed the same as 
has been described for the unscoured leather. The sides are 
sometimes milled, and then they are scoured by means of a 
Monk Scouring Machine, shown in Figs. 50 and 56. The sides 
are now drained and oiled as has been described for unscoured 
leather, or they may be oiled in a mill. They are then hung 
up to dry and when dry they are dipped in water, " sammied," 
rolled and hung up to dry, and when dry rolled again, when 
they are ready to go to the sorter and be selected for the 
market. 

This description is intended to cover modern tanneries which 
use tanning extract. In tanneries where no extract is employed 
the liquor may be several degrees lighter, and the length of the 
" lay-aways " slightly increased. 

In some tanneries the hides are split into sides either as they 
come out of the soaks or out of the limes, especially when the 
tannery has smaller size vats than 7x9 feet. 

The tanning of the whole hide is more economical in labor 
in the yard, but the tanning of sides is more economical in the 
beam-house work. 

The rolling machine shown in Fig. 1 1 1 is the kind generally 
employed for rolling sole leather. The rollers of these 
machines are made of brass, and are six inches in diameter and 
six inches face or length, and are turned to a true surface and 



OAK TANNED SOLE LEATHER. 387 

work into roller beds on concaves, which are also of brass and 
planed true to the radius or length of the vibrator or pendulum 
of each machine. 

The pressure of the rollers upon the leather is imparted by 
means of levers connected with the vibrator or pendulum of 
each machine, and controlled by a lever worked by the foot of 

Fig. hi. 




the operator. The hook to which the foot-piece is connected is 
shown in the illustration of the machine. After the roller has 
passed over a portion of the side two or three times, it is shifted 
by the hand of the operator until all parts are successfully 
operated upon. 

These machines are built by the Eureka Bark Mill Co., Lan- 
caster, Pa. J. A. Brownell, Binghamton, N. Y., builds a good 
under pressure sole leather rolling machine. 

CUT SOLES. 

By the competition in trade many tanners are forced to cut 
soles, which are sold direct to shoe manufacturers. Men's out- 



388 THE MANUFACTURE OF LEATHER. 

soles are cut from packer Texas hides, scoured oak barks. 
Women's outsoles are cut from scoured oak barks from packer 




native hides. The inner sole stock comes from the same class 
of hides, but from that portion which is not good enough for 



OAK TANNED SOLE LEATHER. 389 

outer soles. Goodyear insoles are cut of an oak bark especially 
tanned and finished for that purpose. Counters are made flat 
and moulded. McKay and Goodyear counters are made out 
of scoured oak bellies. Counters for Turn shoes are cut from 
light scoured oak shoulders. 

One of the largest dealers in leather and findings recently 
said that trade in sole leather is carried on very differently from 
a few years ago. Then he had in his store constantly not less 
than 2,000 sides. Now he thinks he is overstocked if he has 
more than 200 on hand. The reason of this is that shoemakers 
buy most of their leather already cut. They can obtain it 
cheaper this way, and the bother of cutting is done away with. 
" Some of my customers in the immediate vicinity," says he, 
"do not carry any leather on hand. When they get a pair of 
shoes to tap they come in and buy the soles for them." 

An interior view of a cut sole factory of Ackerman & Brum- 
mel, New York City, is shown in Fig. 112. 



CHAPTER XXV. 

HARNESS AND BELTING LEATHER. 

NATIVE steer and heavy cow hides, free of brands and other 
blemishes, are used for this variety of leather. The beam-house 
preparation of the hides does not differ materially from that of 
hides intended for heavy upper leather, except that the liming 
should not be as high nor the bating as low as for heavy upper 
leather. 

Harness hides should be thoroughly cleansed from lime be- 
fore they are sent to the tan yard ; this may be easily accom- 
plished without the use of deteriorating excreta or extracting 
the gelatine, but so swelling the fibrine that it will receive the 
tannic acid, and blend readily and perfectly, giving firmness 
without destroying the elasticity or causing a tendency in the 
grain to crack when in use as harness, etc. 

It is absolutely necessary that a thoroughly serviceable 
leather, which ensures the desired softness and pliability, and 
at the same time is free from a tendency to crack or get hard 
in use, should be used in harness making. Harness leather 
must be a great deal more flexible than either sole or heavy 
belt leather, and must have as high a degree of tensile strength 
as can be retained in the course of manufacture, while its sur- 
face must be fine and such as will readily take a variety of kinds 
and styles of finish. Lighter hides are, therefore, used more 
generally than heavier ones, yet, even then, there is no effort 
made to combine with the gelatinous body in the hide-cells as 
large an amount of tannins as the latter will take. A more 
thorough working over of the surface then becomes necessary, 
and a very considerable amount of dressing or stuffing of tal- 
low and grease is, therefore, worked into it, while this, what- 

(39o) 



HARNESS AND BELTING LEATHER. 39 1 

ever the coloring may be, will bring the product, in many 
cases* very nearly to the substance of a leather generally used 
for the uppers of boots and shoes. As we get to the lighter 
leather used for harness purposes, upper leather for boots and 
shoes, and for goods of a miscellaneous character, the tanning 
proper, although always a matter of very great importance, 
loses here some of its former purpose, and the work of the 
currier and finisher then becomes a prime essential in the man- 
ufacture. 

It is perfectly proper that the skins and lighter hides used to 
manufacture these proportionately light goods should not con- 
tain as much gelatinous matter in their cellular tissues as would 
the thicker and, consequently, heavier ones chosen for the tan- 
nage of sole leather ; and they, besides, are not treated with 
tanning liquors of the same concentration as would be required 
for such heavy goods. 

If too concentrated solutions of tannins are used for skins 
and lighter hides, the natural consequence will be that the pro- 
ducts of such a tannage are substances altogether the opposite 
of what we require for saddlery and harness manufacturing pur- 
poses ; flexibility and tensile strength would be lacking. It 
must be admitted that the kinds of the lighter goods in the 
market are much more numerous than are those used for soles 
and for heavy belting, and their qualities vary more widely, 
but by far the larger proportion of the goods made for such 
use — from the skins of calves and partially grown cattle, as 
well as those from larger hides in split form — are tanned with 
the same tanning materials as are used in manufacturing certain 
heavier leather. 

It will not be inappropriate here to make a few remarks on 
belting for lighter purposes, as this is analogous to certain 
parts of harness ; and it must be remarked that, as it should 
have greater flexibility than is found in heavy sole leather, the 
tanner must avoid filling the cells of the hides too thoroughly 
with tannins. If these rules are not observed, the natural posi- 
tion of the fibrous parts of hides may be disturbed. 



392 THE MANUFACTURE OF LEATHER. 

It must be remembered that these fibrous bodies give the 
whole structural substance its tensile strength, although the 
fact may be acknowledged in a general sense only. For one 
thing, it is correct in theory, and it must also have some 
bearing on practice ; and it is certain that it insures to the 
lighter kinds the same tannage, providing the varying precau- 
tions necessary are duly observed. The distinction between 
different kinds, so far as this rests in the substance of the 
texture itself, may be more theoretical than practical when 
viewed in regard to the common usages of the trade, but cer- 
tain important distinctive properties traceable cannot be dis- 
puted. 

All the large hides and sides of patent and enameled leather 
for harness and carriages are split goods, and are generally of 
the largest spread that can be obtained. Three splits are fre- 
quently made, the first being taken from the flesh side, and 
termed "junior." The small splits are usually deficient in 
strength, and cannot therefore be recommended for purposes 
where a fair amount of tensile strength is requisite, or where 
general safety is placed at stake through their use. 

Chrome tannage is now being introduced for the tanning of 
both harness and belting leather, and it makes a strong, tough 
fabric. 

An extract company of West Virginia are the owners of a 
quick tanning process by which they claim to be tanning No. I 
harness leather in 40 days and the best oak sole in 60 days by 
the use of their process and their refined chestnut oak bark ex- 
tract. They have practically demonstrated to many tanners 
that, with the proper use of refined chestnut oak bark extract 
and the new method of handling their hides, the cost of their 
tannage is reduced from 15 to 25 per cent. 

CURRYING HARNESS LEATHER. 

Harness hides and backs, after soaking, should be shaved 
over with care, only taking off the flesh, so as to leave a 
smooth, even surface. They should then be well scoured on 



HARNESS AND BELTING LEATHER. 393 

flesh and grain out of liberal baths of tolerably warm water, 
which opens them and allows them to be better extended and 
slicked out as firm and free from water as possible ; they are 
then ready for the shed. They require to be well set, keeping 
the straight edge in a line with the front edge of the table. 
Two men are generally employed at this work, and each should 
stone so that they cross each stroke, laying the goods out per- 
fectly flat and firm, and then with a thick steel slicker take out 
all the stone and other marks ; then oil them on the grain 
with good oil and turn over for stuffing on the flesh, which 
must be done without folding or creasing the hide or causing 
any contractions. Hides dressed in full length should have a 
loop at each end and one near the centre of the backs to pre- 
vent their drying baggy. When nearly dry they require re- 
setting, the parts that are too dry being damped so that the hide 
or back is equally moist all over, and by keeping the table wet 
before each side is set it will prevent unnecessary removal of 
grease from the flesh. Scarcely too much labor can be be- 
stowed here, as it should be the consolidation of the pattern pre- 
pared in previous stages. The grain should be carefully 
slicked again, so that no tool marks are left, and when dried 
out the sides are ready for blacking, which by some is done by 
brushing them over with urine and soda or fuller's earth, but 
we prefer very hot refuse sumac liquor and fuller's earth, as it 
requires less wetting and is cleaner. Every grease spot should 
be removed or it will not receive the dye, and be the cause of 
much extra labor when it cannot so well be done. They will 
now require the final setting, which will be but very slight if it 
has been properly done in scouring and stuffing. Care is 
again required here to leave no tool marks, and to facilitate a 
good grain surface a heavy glass slicker should be used. They 
should then have a good dressing of tallow dubbin on the grain 
and finished drying, when they may be laid down for stock or 
the grease slicked off, and have a last dressing of hot tallow on 
the grain. This gives a polished surface after laying a short time. 
The same process will be sufficient for brown harness 



394 T HE MANUFACTURE OF LEATHER. 

leather, leaving out the part for blacking, and where the color 
is required to be bright a good sumacing will greatly help it, 
and the stuffing can be adapted accordingly. 

Bridle butts, bellies and shoulders, after soaking, should be 
shaved clean, all the flesh being taken off, then well set out on 
the table with stone and slicker, so as to fully extend them and 
get out all contractions, then be again shaved to the required level 
substance. When they are ready for scouring, some curriers 
object to warm water, but it is very necessary for these goods, 
as it not only aids in cleansing, but it opens or rather mellows 
the fibres so that the leather may be fully extended and laid 
flat ; they should then be placed in a tub or vat, with sufficient 
warm water to cover them without pressure, and be firmly 
slicked out on the flesh and well brushed over and put back 
into rather warmer water than before, but not hotter than the 
hand can be held in, as heat in this state of leather that will not 
injure the flesh of the operator will not injure the article ope- 
rated on. They must now be well scoured on the grain. A stone 
slicker is the best for this part, if not too coarse, and after an 
extra good brushing be put again into clean warm water and 
sleaked out tight on the grain for compoing. We give this 
rather fully, as color depends so much upon how this part is 
done, and cannot be remedied if neglected. They should now 
have a good sumacing, each one being dipped separately and 
quickly while the liquor is hot ; and when all are done, stir the 
liquor up well, as the bottom holds the heat and would burn the 
goods that came in contact with it, though the surrounding 
liquor is cool; and when it is well settled put them in one at a 
time, having sufficient liquor that they are not pressed, and 
pull them out next day ; let them lay an hour and lay them in 
as before, and the next day they will be ready to slick out 
again, which should be thoroughly done. They may now be 
hung in shed for a short time, only sufficient to absorb the 
moisture that would slick out on the table and not approach 
to stiffness or dry in any part, then set them out on the grain 
firmly, keeping the edge of the butts (where cut down the 



HARNESS AND BELTING LEATHER. 395 

back) in a straight line with the table, and leaving no tool 
marks in. Give them a thin dressing of good tallow, dubbin 
and turn over; lay them flat with a thin slicker very lightly, 
stuff them with dubbin made with the best cod oil and pure 
tallow, as stiff with tallow as it can be spread, as its properties 
are the most value in these goods, producing mellowness, 
brightness of color, and facilitating a glossy finish. When they 
are about half dry they should be lightly set and hung up to 
finish drying, and may be sleaked off and glossed when re- 
quired, but will improve by laying a few weeks before finishing. 

The old-fashioned oak bark tannage is still used for harness 
leather ; the best leather is from Chicago packer native steer 
hides, which make a tough and durable leather ; they are clean 
shaved all over and stuffed with pure oil and tallow, carefully 
trimmed and closely selected. 

Curriers' Skirting — This is for finishing skirting and the flesh 
of harness leather in imitation of oak tanning. Take of chrome 
yellow, x / 2 lb.; yellow ochre, 1 lb. ; cream of tartar, 1 oz. ; 
soda, ^ oz. ; paste, 5 quarts ; mix well. This will finish 
twelve sides. 

GERMAN HARNESS LEATHER. 

Green hides, if possible, are used for these varieties. As 
many hides as can be placed in the lime pit are, after cutting 
out the horns, soaked in running water six to eight hours with 
frequent rinsing, next cleansed from dung and placed in weak 
milk of lime for twenty-four hours. They are then taken out and 
replaced, after preparing fresh lime for twenty-four hours more, 
when they are again handled. After this they are regularly 
handled. Depilation is effected as soon as the hair can be 
easily pulled out, after which the hides are soaked in water for 
a few hours. Water stripes and dots are produced by soaking 
the hides too long in running water and allowing them to re- 
main stationary. After fleshing and soaking for twenty-four 
hours the hides are smoothed and placed in the bate for one to 
three days, according to their thickness and the state of the 



396 THE MANUFACTURE OF LEATHER. 

weather. They are handled three times every day they remain 
in the bate. If the England wheel is employed, the bating can 
be accomplished in from eight to ten hours. Special attention 
should be paid to this process, as soft leather can only be pro- 
duced by proper bating, while too much bating is injurious, as 
it destroys the skin fibres and the grain. After taking the 
hides from the bate and rinsing in fresh water they are again 
smoothed, and after soaking for several hours thoroughly 
worked upon the flesh side with a dull fleshing-knife. They are 
then ready for tanning. 

Salted hides of cows and oxen are soaked three days, special 
attention being paid to removing all the salt before placing the 
hides in the lime pit. Dried hides, after thoroughly soaking 
and bringing them back to their original shape by stretching, 
are treated in the same manner as green hides. By using the 
hide mill much labor in stretching and smoothing may be 
saved, and for inferior hides slicking also. 

The handling vats should be sufficiently large to allow of the 
convenient handling of the hides. 

It is generally preferred to place the leather in old liquor for 
one or two days, according to the quality of the liquor in the 
vat. The leathers are taken out and replaced and treated in 
the same manner as above, after ladling out the old tan and 
adding one-third bushel of fresh tan. According to the state 
of the weather the power of the tan will be exhausted in four 
to eight days, it then becoming necessary to freshen the vats. 
After doing this twice or three times more the leathers are 
placed in the lay-aways, where they remain for about the same 
period as for sole leather, a longer period being, as a general 
rule, only required for stout harness and vache-leather, but it is 
absolutely necessary for belt leather. 

In order to see how far tanning has proceeded, it is advisable 
to split the leather after the second layer. The cut of a thor- 
oughly tanned hide will be uniformly brown, while a pale yel- 
low or white coloring is a proof of insufficient tanning. 

After splitting the hides into sides and numbering the two> 



HARNESS AND BELTING LEATHER. 397 

halves with the same number, the completely tanned leather is 
rinsed in old ooze and smoothed with a dull fleshing knife 
upon the beam. Where all three kinds of leather are made, 
the best hides are used for harness leather, the strongest for 
belt leather and the poorest for vache leather. 

The harness leather is gone over with a fine-edged knife and 
then greased upon the flesh side with a mixture of linseed oil 
and tallow and hung up to dry. Vache leather is also greased, 
but only slightly, upon the grain side, and then dried. 

PREPARATION OF VACHE LEATHER. 

The dry hides are soaked in sufficient well water to cover 
them in a vat, handled after an hour, then replaced and allowed 
to soak over night. The next day they are placed upon a 
wooden table, and after tucking in the shanks rolled up, grain 
side in, from the head to the tail, so that every half hide forms 
a roll. The rolls are tied together with strong twine or leather 
straps, so that they will not become unrolled in the succeeding 
beating with fluted wooden mallets, which is continued until 
the hide feels soft to the touch. 

To soften the hides completely they are boarded, after beat- 
ing, upon the grain side with a coarse graining board. After 
working ten or twelve hides in this manner, a thin shaving is 
taken from the flesh side. The best plan is to have two work- 
men perform the above operations, and also the succeeding 
ones. In tanneries provided with a fulling mill, a higher de- 
gree of suppleness can be imparted to vache hides by fulling 
than is possible by beating and boarding with the graining 
board. 

One-half of the hide is then placed upon a somewhat in- 
clined table of wood, slate or glass as long as the hide and as 
wide as one-half the hide, and scrubbed with brushes con- 
stantly dipped in water until the flesh side acquires a mushy 
condition, which can be recognized by the impressions made 
by passing the fingers over the hide remaining visible. It is 
then turned over, and, after placing the back part in a straight 



398 THE MANUFACTURE OF LEATHER. 

line with the edge of the table and passing the hand over the 
hide so that it sticks to the table, the grain side is treated in 
the same manner. 

The slicker is then driven first along the back to prevent the 
wrinkles which are formed from sticking and then in the direc- 
tion from the back to the foreshank. After removing the 
wrinkles, which is absolutely necessary, more force may be 
used for the removal of tan depressions. 

As soon as one-half of the hide is slickered it is immediately 
hung up in the drying loft. If this is higher than the length 
of the hide, the latter is nailed through the hind shank and root 
of the tail to short strong sticks, or incisions are made in these 
places, and after passing through the sticks the latter are placed 
between two poles. 

If the loft is not very high, the back part of the hide is nailed 
to straight, strong poles, which after tying the front and hind 
shanks with twine in such a manner that they cannot hang down 
and form wrinkles, are placed in the pole rack. 

After the hides are partly dry, they are placed separately 
upon the table, and, after wetting slightly such parts as have 
become too dry, one hide is placed above the other and the 
pile repacked. The hides, moistened first, are then replaced 
upon the table, and after fitting the back exactly to the edge 
of the table it is fastened with a few wooden clamps, the im- 
pressions of which are removed later on. 

To remove all tan depressions and to give the leather a 
beautiful appearance and firm touch, the use of a roller is of 
great advantage, especially as it facilitates the currying and 
prevents the grain from being injured by constant working. 

The tan impressions, etc., are then entirely removed, and 
after rubbing with a moist woolen rag, the sides are stamped 
and hung up. 

Before the hides become entirely dry the halves are fitted 
together according to the numbers, and placed grain side upon 
grain side and hide upon hide until a pile is formed, which is 
covered with planks somewhat loaded. 



HARNESS AND BELTING LEATHER. 399 

After remaining here for twelve hours they are hung across 
poles and gradually dried. Each hide is then rolled up sepa- 
rately and about six placed in one bundle, which is secured 
with twine. 

It is scarcely necessary to say that scrupulous cleanliness 
must prevail during all these operations. By strictly following 
the directions given, an article fulfilling all demands will be the 
result, and one which is not only equal to the best Frankfurt 
vache leather, but in most cases surpasses it as regards beauty 
and quality. 

After the harness leather has passed through all the above 
operations, it is sorted into brown and black. The first ac- 
quires lustre by means of a glassing machine or is sold without 
it. The black leather, after grounding with decoction of log- 
wood, is blacked with iron black and, when nearly dry, passed 
through the press. 

The best qualities of light hides from Buenos Ayres, Monte- 
video and Texas may also be used for vache leather. The 
lime used for hides intended for vache leather and inside sole 
leather, is sometimes mixed with red arsenic. This has a 
better effect upon the hide, also softening hard places found in 
these hides, which are always difficult to soften. In using this 
mixture the hides require more frequent handling than in the 
ordinary liming process, and should be depilated as soon as 
possible. As the hides are not raised by the mixture, it may 
also be recommended to subject them to the ordinary liming 
for a day, after taking them from the arsenic and lime liquor. 
This method of liming can also be advantageously employed in 
preparing green hides and kips for upper leather, but the after 
liming must be contiuued for a correspondingly longer time. 

DRUM TANNAGE. 

Drum tanning for harness, strap leather, etc., is growing 
steadily in favor. If properly conducted, drum tannage pro- 
duces leather fully equal to that produced by older methods, 
both as regards quality and appearance. There is no doubt that 



400 THE MANUFACTURE OF LEATHER. 

this mode of tanning would be far more generally practiced 
than is actually the case, were it not for the heavy royalties 
exacted by the owners of the patents and for the fact that 
a powerful motive and mechanical equipment, available in 
very few tanneries, is required. Tanneries constructed in 
future specially for making these kinds of leather will, how- 
ever, henceforth doubtless have to be planned with a view to 
drum-tanning. 

INDIAN HARNESS LEATHER. 

In an article by Walter G. McMillan, read before the Society 
of Chemical Industry, the author stated that the Director Gen- 
eral of Ordnance in India asked him to undertake a series of 
mechanical tests with the object of ascertaining the tensile 
strength of harness leather made in the Government Harness 
and Saddlery Factory at Cawnpur, and to compare it with 
that of samples made in private tanneries in Madras and in 
England. Several hundred tests of various kinds were made, 
and it is proposed, with the sanction of General Walker, to 
summarize the more useful of these results in this short 
paper. Visits to the Cawnpur factory have enabled the writer 
to give a sketch of the system of tannage by which the 
leather was made, and thus to give additional interest to the 
research. 

The factory is worked by the Ordnance Department of 
India, under the immediate superintendence of officers of the 
Royal Artillery. The foreman is an experienced English 
tanner, and he is assisted by several staff sergeants instructed 
by him in such details as are required to enable them to 
supervise the native workmen in their own departments. The 
tannery is of no mean size, there being usually from 35,000 to 
40,000 hides under treatment in the tanyard at a time. The 
currying and the subsequent fashioning of the leather into 
harness and saddlery components are conducted in the same 
establishment. 



HARNESS AND BELTING LEATHER. 40I 

THE SYSTEM OF TANNAGE USED IN THE CAWNPUR FACTORY. 

The factory is situated on the banks of the Ganges, close to 
the point at which it is joined by the Ganges Canal, and it is 
from this latter source that the water supply is drawn. The 
following numbers are the results of an analysis of water from 
this canal made by Dr. Compigne in the autumn of 1867, and 
recorded in a Government publication : 

Degree of total hardness 4.7 

Degree of permanent hardness 2.8 

Solids in 70,000 grains of filtered water 8.26 

Mineral matters 7.56 

Earthy salts, etc., insoluble in water 5.07 

Lime as carbonate 2.6 

Soluble salts 2.5 

Sodium chloride 1.5 

With the exception of the somewhat large percentage of 
suspended matter — a difficulty met by allowing the supply to 
stand in settling tanks before use — the water appears to be 
suited for the work of the place. 

The hides are for the most part buffalo and cow hides, 
which come to the factory from different parts of India very 
lightly salted, while a few are obtained green from the Cawnpur 
butchers and require immediate treatment. They are said to 
be fairly well flayed as a rule, with but few flesh cuts and little 
fat. Occasionally, careless handling prior to salting is found 
to have produced local putrefaction, which greatly deteriorates 
or destroys the skin, and is made apparent in the lime pits, 
even if it had not declared itself previously. 

The tanning material used has generally been Babul (Acacia 
Arabica) bark, with a small proportion of myrobolans ; within 
the last few months valonia has been substituted for the latter, 
but all the Cawnpur leather referred to in this paper was made 
with the addition of myrobolans. A few experiments were 
tried with a view to introducing the use of Sal (Shorea Ro- 
busta) bark in place of Babul, but the leather so prepared was 
somewhat hard and dark colored, and gave a distinctly inferior 
26 



402 THE MANUFACTURE OF LEATHER. 

test, as the numbers quoted hereafter will show. Babul bark, 
which is abundantly obtainable from local contractors, has been 
found by Christy to yield 18.95 P er cent, of a good cream- 
colored tannin. A sample given to the author on the occasion 
of his visit to Cawnpur in 1893, gave 21 per cent, of tannin, 
while a specimen of Sal bark yielded only 9 per cent. The 
bark is said to be of fairly constant strength, showing only a 
slight loss of tannin (by exposure) during the rainy season. 
The exhaustion of the bark is effected in latches, which are 
worked in series of eight, giving different solutions, with a 
range of from 2 to 50 degrees barkometer. The latches are of 
brick, with wooden false bottoms, and are of three different 
sizes in different sheds. The sizes and weights of material 
employed are as follows : 

Charge of 
Charge of Bark. . Myrobolans. 
Size of Latch. Cwt. Cwt. 

1 2x10x8 50 15 

10x10x8 50 15 

10x9x8^ 35 io 

The tan liquors are returned to be refreshed to one or other 
of the latches, according to the strength indicated. 

The tanning process is conducted as follows : 

The hides are soaked in pits in which the water is changed 
whenever, from its appearance, it is judged to require renewal. 
They are then stocked for about half an hour in a gentle stream 
of running water. 

They are next limed in a series of six pits, each fresher than 
the last. The lime pits are, as usual, worked in a rotation, 
being made up originally with 5 cwt. of lime to the pit ; this 
liquor lasts for about a month without further addition of lime, 
and treats 700 or 800 hides. Each hide may remain in the 
lime for from 15 to 18 days, but in the hottest weather a some- 
what shorter soaking suffices. 

They are now unhaired and fleshed, and are then bated in a 
liquor made up by extracting seeds from the pods of the babul 



HARNESS AND BELTING LEATHER. 403 

tree with water. This bate has originally about 2 cwt. of the 
seed to each pit, and lasts about three weeks ; a gentle fermen- 
tation is initially set up by the addition of a few buckets of tan 
liquor. For light leather a bran bate is generally substituted. 
The process demands careful attention at all times, but par- 
ticularly in the hot season. 

The hides are now at once transferred to handlers containing 
weak liquors (7 to 8 degrees) for two or three days, being 
handled every two or three hours during the first day. The 
spent liquors from this vat are allowed to run to waste. After 
this the skins are handled daily for about a month in stronger 
liquor (15 degrees), then for a month in "floaters" in liquor 
of about 20 degrees ; next they are transferred to " dusters," 
working at a strength of 30 degrees and containing a small 
proportion of fresh bark ; here they are handled daily for from 
one to two months, and are then put away for about six months 
in layers, the liquor strength in which varies from 35 to 50 de- 
grees, but averages 45 degrees. Each layer pit contains, in 
addition to the liquor, 4 cwt. of bark and 2 cwt. of myrobolans, 
and treats 100 hides. 

CURRYING. 

The hides are now transferred to the curriers' shops, where 
they are successively shaved to the required thickness, scoured 
on flesh and grain, passed rapidly through weak sumac liquors, 
oiled with cod oil, sammied and struck out, reshaved or flatted, 
stuffed with a mixture of cod oil and tallow (in equal parts in 
the cold season, but containing 60 per cent, of tallow in the hot 
season) and are finally dried out and finished by the removal 
of surplus grease. 

In all the processes here described the average treatment 
has been given, but this must of necessity be greatly modified 
at different seasons in a climate which is equivalent to an Eng- 
lish summer in the cold weather, where the thermometer may 
daily rise for several months to over ioo° F., when a very 
small proportion of atmospheric moisture exists, and where for 



404 THE MANUFACTURE OF LEATHER. 

two or three months the atmosphere may be saturated with 
water vapor with a thermometer indication of over 90 degrees. 

Concerning the processes used in the preparation of the 
Madras and of the English leather, the author has no informa- 
tion. The latter leather, however, was taken from a large num- 
ber of hides supplied to the Government by a good firm of 
English tanners. 

The tests to be described were made chiefly with new leather. 
Half hides were supplied to the author's department and were 
cut, under his direction, in the manner detailed below. A cer- 
tain number of the Cawnpur (Babul and Sal-tanned) English 
hides were made up at Cawnpur into harness components, 
were issued to a battery of artillery, and, after six months' ser- 
vice, were returned for test, and were then cut up into straps 
of suitable shape and size for the testing machine. The testing 
machine was one of Greenwood and Batley's lever pattern, and 
although intended and generally used to test metallic speci- 
mens up to a 100-ton load, was yet equally well adapted to the 
measurement of any stress exceeding 500 pounds. 

TESTS OF NEW LEATHER. 

The half skins being submitted, straps measuring in the test 
portion 10 inches in length by 2 inches in width, were cut 
from different positions in the hide. 

The results of the tests were that the Cawnpur hides, as com- 
pared with English and Madras hides, both heavy and light, 
showed 8 to 10 per cent, greater strength at the average break- 
ing stress and less stretch. The English hides showed greater 
resistance when wet than either the Cawnpur or Madras. The 
most absorbent and least dense leather in regard to water was 
the Cawnpur, next the Madras, and last the English. It was 
found that the narrower straps were proportionately stronger 
than a wide one, and that the weakening of a strap produced 
by the perforations to receive the tang of the buckles was 
nearly one-half. 

Finally, to bring to a focus a few of the points which appear 
to be indicated by the experiments quoted in the paper : 



HARNESS AND BELTING LEATHER. 405 

A. In comparing the leathers produced by the two systems 
of tannage, that which had the lower specific gravity (wet or 
dry) was to a marked extent more absorbent than the other, 
and was at the same time stronger both actually and per square 
inch of section, but stretched less before rupture. 

B. In leather produced by a green system of tannage. 

1. Thin hides are stronger per unit of sectional area than 
thick hides, while the ultimate extension before rupture, al- 
though practically the same, is on the average slightly greater 
in the stouter specimens. 

2. Thin hides are more absorbent and have a lower specific 
gravity when wet than thick hides. 

3. In any given hide, omitting from consideration the ex- 
treme neck portion of the back, which is altogether inferior, 
straps from the rump half should carry a higher actual load by 
reason of their greater thickness, but will nevertheless stand a 
lower stress per square inch than those from the neck half. 

4. With average hides, a comparison of strength per unit of 
sectional area is permissible, but shaving or an exceptionally 
severe use of the fleshing knife may lower the strength per 
square inch of section, while it increases the extensibility. 

5. Other things being equal, a narrow strap may be ex- 
pected to be not only stronger than a wide one, both actually 
and per unit of sectional area, but also to stretch more under 
a given load. 

MACHINE BELT LEATHER GREASED WITH TALLOW. 

By greasing with tallow this leather acquires the desirable 
property of not becoming hard, even if the belt cut from it has 
to pass, as is frequently the case, through water. This leather 
is tanned in the same manner as has been described for sole 
leather, complete tanning being the principal requisite. 

After dividing the hides into sides and rinsing off the tan, the 
sides are scoured either by hand or machinery, so as to pre- 
pare them for the reception of the tallow. The sides are then 
treated differently from the leather that is to be used for uppers 



406 THE MANUFACTURE OF LEATHER. 

of boots and shoes, in that they are not dampened and tem- 
pered, as has been described for heavy upper leather. But the 
sides, after being scoured, are dried in heat — in summer by 
spreading them out and exposing them to the direct rays of the 
sun, and in winter in a room having a temperature of at least 
no° F. 

Pure, best ox tallow, is melted in the meanwhile in a port- 
able boiler, a temperature of \6j° F. being the best for the 
purpose. This temperature should be kept up after the tallow 
is melted, which can be effected by keeping the boiler over a 
small coal fire, or, still better, by placing it in another boiler 
with hot water, which is kept hot over a fire while the work is 
going on. 

One of the heated sides is then placed upon the table and 
the fluid tallow applied with a brush. The hide should be so 
thoroughly saturated with the tallow as to be entirely per- 
meated with it, and the tallow applied to the flesh side so as to 
become visible upon the grain side. Should the tallow congeal 
upon the surface before permeating, it is allowed to soak in by 
placing the hide in the sun or near a warm stove ; but if the 
hide is already thoroughly permeated, the excess of tallow 
must be removed. 

CURRYING THE TALLOWED LEATHER. 

The sides having lost their good appearance and become 
dark by greasing with tallow, are soaked in water for twenty- 
four hours and then placed upon the beam, and the tallow still 
adhering to the flesh side is removed with a blunt knife. After 
placing them again in water, each side is taken out separately, 
and after spreading it upon the table and covering with a layer 
of spent tan one-half inch thick, it is rolled up, and the roll, 
after securing it with twine, beaten with a mallet, until the 
leather has again acquired a light color and its original 
suppleness. 

After rinsing off the tan the hides are again beaten, with 
frequent dipping in water in case they should feel too dry. 



HARNESS AND BELTING LEATHER. 407 

They are next smoothed in the same manner as for the 
ordinary machine belt leather. 

It is recommended to have two men to do the work, it 
being too fatiguing for one. 

• The manufacture of this variety of leather, though very 
laborious, repays doubly the work expended upon it, princi- 
pally by the increased weight the leather acquires by the 
absorption of tallow. 

CURRYING STRAP BUTTS FOR MILL BANDS AND ENGINE BELTS. 

Strap butts for mill bands and engine belts are generally 
made from good domestic hides, and sometimes from foreign 
of good growth, which have not been struck out nor rolled as 
sole leather, but merely dried out of the pits. The first thing 
to be done is to thoroughly soak them ; they should then lay 
down two or three days to mellow, and then be shaved lightly 
over, only the rough flesh being taken off, the substance not 
being reduced. Some do not shave them at all, saying where 
a scouring machine is used that will take off sufficient ; but 
straps and belts made from these manufacturers' butts are not 
so good in either wear or appearance. After shaving they 
should be put into water and lay at least one night and be well 
scoured first on flesh, then on grain, and be hung in shed to 
stiffen previous to being put in the stretching machine. Much 
attention is required at this stage that they be dry enough to 
retain the full surface acquired in straining, and not too dry to 
receive a fair quantity of dubbin in such a state as to amalgamate 
and form part of the leather. We have heard some professed 
curriers say the stretching is unnecessary and that they dispense 
with it, but their belts when made are far behind first-class, and 
must stretch themselves in use. Before the butts or sides are 
fixed to the machine we prefer having them well set on the 
table on the grain side, the flesh side having been brushed 
over with dubbin sufficient to cause it to adhere, and yet ex- 
pand as it is worked upon. It will then be in a better state for 
yielding to the pressure required than if done after stuffing, and 



408 THE MANUFACTURE OF LEATHER. 

should be lightly set after taking out of stretcher, and brushed 
over with dubbin and laid in packs ready for stuffing, which 
may be done when all are ready and hung to dry. These 
should be dried out before resetting, though they must be 
damped down after and then well set, and when re-dried should 
lay away a time before finishing. A good coat of tallow on 
the grain before laying away improves the quality and appear- 
ance. Where the butts are not stretched by machine, they 
should after scouring be well set out on the grain before 
stuffing, and when rather more than half dry be taken down 
and thoroughly set out on the grain, and then dried out and 
reset before laying down in stock, ready to be finished when 
required. 

TO REMOVE GREASE FROM LEATHER BELTING, ETC. 

The following method of removing grease from leather belt- 
ing is patented in Germany and consists in subjecting the belt 
to a slow, dry heat after packing in dry powdered clay. 

The belt to be degreased is rolled up in a spiral in such a 
manner as to leave from ^ to x / 2 inch space between each con- 
volution. It is then placed in a specially constructed box or 
other receptacle, the bottom of which is covered with a layer of 
powdered clay, and the space between the belt and the sides of 
the box, as well as the space between the convolutions of the 
spiral, packed tightly with powdered clay, the whole being 
lastly covered with a layer of the same. 

The object of packing in the clay tightly, as described, is 
two-fold, viz. : To prevent warping and to insure contact with 
the clay at every point, and consequent perfect cleansing of the 
belt. The box with contents is introduced into an oven, 
specially constructed so as to give out an even heat from all 
directions, the latter being an important point, as irregular 
heating will warp and spoil the belt. The baking process is 
kept up until all grease has been extracted, which takes from 8 
to 10 days, according to how long the belt has been in service, 
and the degree of heat to which it is subjected. The hotter the 



HARNESS AND BELTING LEATHER. 409 

oven, the quicker the operation, but it is not advisable to risk 
using too much heat, as the belt might thereby be easily ruined. 

When satisfied that all the grease has been extracted, the 
box is removed and allowed to cool off gradually, or, better 
still, is left to cool off with the oven. A gradual cooling-ofif is 
absolutely necessary, as a sudden degree of temperature will 
warp and injure the belt. The precautions necessary to a suc- 
cessful result, the omission of all or one of which is fatal, are : 
Care in packing the clay closely and tightly ; evenly distributed 
heat, and gradual cooling off. 

The above process not only removes every trace of grease, it 
is said, but also acts as a preservative and stops all further 
stretching, one of the disadvantages of new belts. Being a dry 
process, it can be applied without injury to cemented belts. 

WET STRETCHING MACHINE FOR BELT LEATHER. 

Figs. 113 and 114 show a vertical section and elevation of 
a wet stretching machine for belt leather built by the Vaughn 
Machine Company, Peabody, Mass. This machine is for wet 
stretching belt leather and it will do the work thoroughly, tak- 
ing out all the stretch and gaining largely in measurement. 



41 THE MANUFACTURE OF LEATHER. 

Fig. 113. 




VERTICAL SECTION OF WET STRETCHING MACHINE FOR BELT LEATHER. 



HARNESS AND BELTING LEATHER. 
Fig. 114. 



411 




WET STRETCHING MACHINE FOR BELT LEATHER. 



CHAPTER XXVI. 



DANISH LEATHER. 



UNDER the name of "Danish leather" is sold on the market 
not only glove stock but also leathers for various other pur- 
poses. Owing to its extreme suppleness, as much as owing to 
its beautiful color, this product has long stood in especial favor 
with consumers. 

These desirable traits of Danish leather are secured mainly 
by a most careful preparation of the hides preparatory to tan- 
ning, thorough and favorable soaking and cleansing, combined 
with the use of willow bark as tanning agent. 

It is hardly necessary to say that the best " Danish leather," 
so-called, comes from Denmark proper. In that country 
spring water is a rarity, and the many small streams and lakes 
are mainly fed by rain-water ; the water is very soft, and par- 
ticularly well adapted for the production from raw material 
treated with it of a pliable leather of most excellent feel. On 
the borders of these same streams and lakes thrive those very 
species of willow, whose valuable bark is almost exclusively 
used in tanning throughout Denmark. 

The leather obtained by this willow tannage is of a light red,, 
pleasing to the eye, and is readily worked into colors, yellow 
and brown shades being favorites among manufacturers. 

Otherwise the tanning and currying differs but little from 
ordinary processes for upper leather, the main secret of success 
lying in the painstaking manner in which every detail of the 
handling, from raw hide to the finished article, is followed up. 

Danish leather, even when intended for saddlery purposes,, 
receives but little addition of grease, glycerine being used in- 
stead for softening purposes. This is a method comparatively 

(412) 



DANISH LEATHER. 413 

little known in connection with the manufacture of other sorts 
of leather except kid, and is applied as follows : By means of 
a sponge a very thin coat of glycerine is rubbed over the flesh 
side of the leather, which latter is then folded, flesh-side in. 
The glycerine by simply penetrating the leather, serves to re- 
tain its pliability. Frequently, it is true, a tanner will add a 
small proportion of grease to the glycerine, or give a light ap- 
plication of grease to the leather after it has become impreg- 
nated with the glycerine. 



CHAPTER XXVII. 

RUSSET LEATHER. 

RUSSET leather is usually made from rough leather which is 
very carefully selected for shoe leather, so as to get it free from 
imperfections, such as brier scratches, grubs, salt stains, tan- 
ners' hook marks, chafed grain, arising from rough-edged 
workers in working out of the drench and from the short hair- 
ing knife. 

Leather which is selected for bag leather and printed with a 
large figure does not show up the imperfections so plainly ; 
and consequently, a lower grade of leather can be used for this 
purpose. 

Large sides are used for bag leather and for strap leather, 
while the smaller sides are used for shoe purposes. The sides 
employed for strap leather may have some imperfections, but 
these imperfections may be dodged in the cutting. The sides 
selected for card leather and for shoe leather must be pretty 
nearly perfect. 

The leather used for United States mail bags is russet, as is 
also the leather used for the bags carried by the U. S. letter 
carriers, and they may have more imperfections than card or 
shoe leather. Leather which is used for ladies' belts must be 
free from imperfections if the belt is not embossed. If it is em- 
bossed, it covers up a lot of the minor defects. 

The russet leather which is used for bicycle seats and cases 
must be of high grade. The light russet leather used for whip- 
stocks should be of good grade. The light russet leather used 
for book-bindings should be high grade. There are a large 
number of sheep-skins used for this purpose, but bindings of 
this character chip easily and are not so good as the light 

(414) 



RUSSET LEATHER. 415 

russet leather. The highest grade of book bindings is made 
from calf-skins. Book bindings are also made from large and 
thick sides of leather which are then embossed and finished in 
imitation of seal and natural grains, and then split down very- 
thin, about one ounce to the square foot, so as to give the ap- 
pearance of a heavy, solid leather without the weight. 

The straps which are used in street cars to hold to when the 
cars are crowded, as well as belt straps and register straps, 
must. also be of high grade russet leather. Russet leather is 
also used for a large variety of purposes which have not been 
mentioned. 

When the rough leather is selected and delivered to the 
currier, the first thing is to round it by cutting off the shanks, 
tails, teats, snout and other waste parts. The sides are then 
wet down and allowed to mull for about twelve to twenty- four 
hours. Then they are put into a pin-wheel and milled for ten 
minutes, so as to take out the stiffness and get them into better 
condition for working. They now contain about fifty per cent, 
of water, and are skived in this condition by running them 
through the belt knife splitting machine. The skiving is 
simply for the purpose of taking off the loose flesh, and, at the 
same time, giving a more even surface to work upon, and it also 
improves the appearance of the split, which is later on taken 
from the leather, and which, in most instances, is sold in the 
rough" to the split finisher. The sides are then worked on the 
grain side on the stoning jack made for this special purpose, 
by J. T. Freeman & Co., Woburn, Mass., to take out the stretch 
and creases in the grain previous to splitting. 

The sides are next piled on a table and sorted for thickness. 
They are usually divided into light, medium and heavy. Then 
the splitting machine is adjusted so as to take the lightest sides 
first, the medium next and the heavy last. The knife of the 
splitting machine is wearing back all the time, so that when the 
heaviest sides are fed to the machine the edge of the knife is in 
the right position. 

The proper way to split shoe leather is to preserve the nat- 



41 6 THE MANUFACTURE OF LEATHER. 

ural lines. The side of leather will finish best split with a grad- 
ual taper from back to belly and from butt to shoulder. 

Card leather and strap leather have to be split pretty nearly 
of a uniform thickness. The leather is next given to the shaver, 
who cuts it over lightly on the flesh side to take out any little 
marks or inequalities left by the belt knife. The leather is then 
put into the pin-wheel with a weak solution of borax or other 
alkali and washed thoroughly. While it is still in the wheel, it 
receives a bath of weak sulphuric acid or other acid to neutral- 
ize the alkali and, at the same time, take out any iron stains 
that may be in the leather. 

The borax bath is drawn off before the sulphuric acid bath is 
applied. The alkali bath works out the dirt and makes the 
leather appear much darker. The sulphuric acid bath changes 
the color of the leather to a much lighter shade than it was 
originally. 

The sulphuric acid bath is then drawn off, and the leather 
receives a warm bath of Sicily sumac and alum, which makes 
the leather of a still lighter shade and at the same time softens 
it. The leather is then rinsed in clear water in a tank and is 
immediately struck out on the flesh side to remove the water 
and surplus sumac. 

The leather is now in condition to dye or leave in the natural 
light color which has been obtained. If the light color is de- 
sired, the leather is hung up and allowed to harden, as it is 
termed in the East, or to sammy, as it is termed in the West, 
for setting. The setting is done by swabbing a table over 
lightly with oil, or paste, if no oil is desired in the leather. 
Then it is set out on the grain side with a setting stone, and 
afterwards with a brass slicker, to take out the stone marks. 
The leather is then hung up. Some tanners hang it on half 
round sticks ; others suspend it by the head and butt with 
strings and allow it to dry. If the leather is to be printed, it is 
next dampened with clear water or flax-seed gum or egg albu- 
men or milk, and is printed with whatever figure is desired. 
After it is printed, it is grained with a cork arm board and 



RUSSET LEATHER. 417 

hung up to partly dry. Then the leather is taken down and 
soft-boarded and hung up to thoroughly dry. After it is dry, 
it is staked by the staking machine. Then it is glazed with an 
agate or glass machine, and then it receives the final graining 
and is ready for market. 

If the leather is to be dyed, it is put into a vat after it is 
struck out. The vat is about six feet square, and has a circular 
bottom and a paddle wheel about five feet long and four feet in 
diameter, hung upon a shaft about two inches in diameter, with 
fast and loose pulleys. This paddle will run from eighteen to 
twenty revolutions per minute. The vat usually stands about 
one foot above the floor, so as to draw off the exhausted dye. 
The vat is about five feet deep, and is partitioned off at one 
corner with a well about ic/'xio", which runs to the bottom 
of the vat. The well is pierced with auger holes, and the strong 
dye is put into the vat through this well and mingled uniformly 
with the water in the tank. 

The leather has already been partially mordanted by the 
sumac and alum for certain shades. Some colors do not re- 
quire any further mordant; but others do. The colors used 
are mostly anilines. The secret, if any, in dyeing leather is in 
preparing it for dyeing. Russet leather is dyed in a great vari- 
ety of shades. As many as a dozen different shades, or more, 
may be obtained from the same can of color. After the dyeing 
is done, the leather is struck out on the flesh side and fat- 
liquored in the pin-wheel, and hung up to harden or sammy 
previous%k> setting. The leather is then finished in about the 
same way as the light-colored leather which has been described. 
27 



CHAPTER XXVIII. 

GRAIN AND SPLIT LEATHER. 

SATIN OIL FINISH ; OIL GRAIN ; PLOW GRAIN ) GLOVE GRAIN ) IMITATION 

GOAT OR PEBBLE GRAIN ; IMITATION KANGAROO J IMITATION SEAL ; 

IMITATION HOG \ WAX CRIMPING SPLITS ; FLESH SPLITS ; DON- 

GOLA, BUFFED LEATHER AND FLEXIBLE SPLITS, WITH 

STUFFINGS : PASTES, BLACKS, FINISHES, ETC. 

In upper leather, buyers look for softness, suppleness, pli- 
ability, elasticity and waterproof quality ; in bending it must 
not break, must have a nice grain and good color; it must be 
well worked, staked and grained and possess durability; it 
must have a full and plump feeling, it must have a delicate 
lustre, and the dear only knows what more is expected. 
Besides the above qualities, the buyer also looks for a fine 
grain on black leather, and this must be uniform, for leather can 
be considered handsome only when it is uniform. A uniform 
grain insures it against uneven contraction. By considerable 
work in slicking and setting out during the currying, these 
irregular grains may be worked out, but in graining or board- 
ing it will always appear again to a greater or less extent, and 
never can be entirely remedied. This false, uneven grain may 
be prevented in two ways, that is by using weak liquors at the 
beginning of the tannage and by continued agitation while the 
skins are in the first liquors. In the first instance there is too 
little tannin in the liquor to cause a strong contraction of the 
grain, and in the second the constant bending of the skin by 
the agitation breaks the grain in every direction and prevents 
any break in one direction only. How nicely the grain is 
broken by agitation one can best see illustrated in English 
crown leather, where the grain in consequence of the constant 
stretching and lifting of the wheel becomes so regular that fur- 

(418) 



GRAIN AND SPLIT LEATHER. 419 

ther currying is not necessary, and the hide, so to speak, comes 
finished from the wheel. The stronger the liquor is the more 
apt it is to contract the hide. It is very injurious to commence 
the tannage with too strong liquors, and equally injurious to 
allow the liquors to fall away in strength. Commence with 
weak liquors and strengthen them, keeping up a constant agita- 
tion, until the grain has been formed, and the leather is so far 
tanned that the grain cannot contract. 

Satin oil finish, oil grain, plow grain, glove grain, imitation 
goat or pebble grain, imitation kangaroo, imitation seal, imita- 
tion hog, wax crimping splits, flesh splits, dongola and buffed 
leathers are produced in large quantities in the United States in 
Massachusetts, New York, Pennsylvania, Illinois, Michigan and 
Wisconsin. 

The bark used for the tannage of these leathers is hemlock, 
and is derived principally from Pennsylvania, Michigan, Wis- 
consin and Canada. 

The hides used are chiefly slaughter hides, and are obtained 
from Chicago, Illinois, St. Louis and Kansas City, Missouri, 
Cleveland, Dayton and Cincinnati, Ohio. Boston, Massachu- 
setts, and other points in New England furnish a few hides, but 
the supply from the latter sources is small. 

The hides used for the varieties of leather under considera- 
tion are "buff" hides," i. e., those obtained from cows, heifers, 
and steers, and will average to weigh about fifty pounds each. 

The first step in preparing them for the tanning liquor is to 
place the hides in the soaks of clean, cold water, and here they 
usually remain two or three days, the water being changed 
every day. 

In soaking the hides they are placed on a stick the length of 
the back-bone, then they are hung low enough in the pit to be 
covered by water, which does away with the hoisting of the 
hides out of water. The plug is drawn each twenty-four hours 
and the water run off. The vats are rinsed of salt and sedi- 
ment and fresh water run in. 

The pits must be fixed for this process by a stick on each 



420 THE MANUFACTURE OF LEATHER. 

side with pins far enough apart to admit the sticks upon which 
the hides are hung, and low enough to be covered by water. 

After being removed from the soaks the hides are split into 
sides, and after being split the sides are fleshed by machinery, 
and are then rinsed in clear water and are toggled or tied to- 
gether and then placed in the limes, where they remain for 
from five to seven days, being reeled into a vat of stronger 
lime each day. The power reel is used in some factories and 
the hand reel in others. 

The limes must be cleaned every 14 days, beginning at head 
lime and cleaning every other day. This gives clean limes 
every 14 days, and the hides come out uniform from the limes 
and are ready for the bate and the wash reel. 

The object of liming is to get the hair off, not to eat the 
gluten of the hide up. The sooner you lime and get the hair 
off, the less bating required. If you eat the gluten out you 
have nothing to build on for weight. This gives more weight 
and a closer and finer split, better flanks and heads. 

The sides are next unhaired, which is accomplished usually 
by the machine process. Eight hundred sides of leather can 
be unhaired in one day of ten hours by the machine method. 

When unhaired by machinery the sides are passed through 
a Vaughn or Whitney unhairing machine, and are then re- 
fleshed by machinery to take off the flesh "puffed up" or 
raised by liming or left on after the first fleshing. 

The unhairing, fleshing and refleshing machines are fully ex- 
plained and illustrated in Chapter VIII. 

When the sides are unhaired and fleshed in this manner by 
machinery they are placed in a bate of hen manure (but pigeon 
manure is better), in which they remain from twelve to thirty- 
six hours, but when the sides are worked in the bate with the 
England wheel shown in Figure 35, the bating can be accom- 
plished in six to eight hours, the time depending upon the 
weight of the hide and other circumstances, the object of the 
bate being to fully neutralize the lime, thereby giving a 
smoother grain to the leather. 



GRAIN AND SPLIT LEATHER. 42 1 

After being removed from the bate, the sides are allowed to 
remain over night in a vat of clean, cold water, and are then 
worked out and short haired and washed in a wheel with a 
stream of water heated to 70 F. for two to three minutes. 
When the water runs off clear from the wheel it should be 
stopped, as the object of the washing is then accomplished. 
The sides are then tacked to sticks and suspended in the 
" handlers," containing hemlock liquor, which is increased from 
about three degrees strength at the start to twelve degrees 
strength at the finish. The sides are treated in these handler 
vats for about twenty-two to thirty days, being shifted contin- 
uously or daily into stronger liquor. Some manufacturers al- 
low a small stream of liquor to run continuously into the vats ; 
others strengthen the liquor daily. 

After being removed from the sticks, they are allowed to 
drain for a few hours and are then pressed in a power press 
sufficiently dry for the splitting machine. They are next 
skived, usually by a belt-knife machine shown in Chapter XIII., 
one man being enabled by a machine of this character to skive 
1000 sides in one day of ten hours. They are then stoned out 
on a Vaughn machine (Chapter XVI.), similar in construction 
to the setting-out machine; which machine will stone out 
1000 sides a day, or on a stoning jack, shown in Fig. 39. They 
are then fitted or trimmed on a table with an ordinary shoe 
knife and are next split, usually by the same kind of a belt- 
knife machine which has been mentioned. Two men will split 
from 500 to 1000 sides in one day of ten hours ; about 2 T / 2 to 6 
ounces grain to the square foot being usually taken off the 
side in splitting it, depending upon the kind of leather which 
it is desired to produce. 

The " split" is then trimmed by hand, and is then run in a 
pin-wheel with weak liquor for 15 or 20 minutes to take off the 
glaze caused by splitting, and then placed back in liquor of 
about eight degrees strength, which is gradually increased and 
remains for from twelve to fifteen days and sometimes longer. 

The part from which the " split " is taken, called the "grain," 



422 THE MANUFACTURE OF LEATHER. 

is shaved on a beam with a currier's knife in order to take off 
any flesh or lumps which may be left on the thin flanks. One 
man will shave from fifty to five hundred sides in a day, de- 
pending upon the amount of work which the shaver has to do ; 
sixty sides being a regular day's work, provided they are 
shaved all over. 

They are then milled with either sumac or hemlock liquor, 
or both, for about one-half hour in a revolving drum, which is 
commonly about eight feet in diameter and four feet wide. 

After being removed from the liquor they are next scoured 
in some few establishments, but scouring, unfortunately for the 
quality of the leather, has become a thing of the past in many 
of the large factories. After being scoured, if this is done, the 
sides are hung over poles and exposed to the air to harden, as 
shown in Fig. 115. They are then taken down from the poles 
and the dry spots dampened and are piled, and left to equal- 
ize for twenty-four hours. They are then carried to the shop 
and stuffed in a revolving drum, such as has been explained 
and illustrated in Chapter XV. ; the operation of stuffing lasting 
from about thirty to sixty minutes ; the drum being at a tem- 
perature of 160 F., and the grease at a temperature of 140 F. 

Tannages are not all alike and of course cannot all be 
handled alike. The leather ought to be from three to four 
days ahead of the mill so as to be well mulled. Sometimes the 
leather is a little damper, then the mill and grease both ought 
to be a little hotter and run somewhat longer. In hot weather 
the leather must be turned every day to prevent heating. 

After being stuffed, as soon as they are cool, they are thor- 
oughly set-out, hung up and dried. They are then buffed and 
whitened, the grains are buffed and the splits are whitened. 

These leathers are all stuffed differently. Satin grain, four 
ounces to the square foot, is stuffed from 40 to 45 per cent, of 
its wet weight; the stuffing being 35 per cent. English degra's, 
35 per cent, brown grease, 15 per cent, stearine, 15 per cent, 
wax. / 

Glove grain, four ounces to the square foot, being stuffed 



GRAIN AND SPLIT LEATHER. 



423 




424 THE MANUFACTURE OF LEATHER. 

about 25 to 35 per cent, of its wet weight according to its tan- 
nage. The stuffing is composed of 35 per cent. English degras, 
65 per cent, brown grease. 

Imitation goat or pebble grain, 4 ounces to the square foot, 
is stuffed lighter still, from 15 to 20 per cent, of its wet weight. 
The stuffing is composed of 30 per cent, degras, and 35 per 
cent, paraffin oil, and 35 per cent, cod oil. 

Kangaroo and dongola are stuffed 20 per cent, with French 
degras. This is all the stuffing they get until they go on the 
setting-out table, when they receive a coat of cod oil on grain 
side. The next day, after being stuffed, the sides are set out, 
this now being done by the large firms with machinery. 

The Vaughn setting-out machine for splits and stuffed leath- 
ers is shown in Chapter XVI. It is built by the Vaughn Ma- 
chine Co., Peabody, Mass. 

The sides are then struck out on the flesh by hand with a 
thin, sharp slicker, and then hung up to dry. They are taken 
down when dry and carried to the finishing room and stained 
on the grain side with a preparation of logwood and soda ; one 
pound of logwood chips to one gallon of water, two ounces of 
sal soda being used to the gallon of staining. The sides are 
then immediately blacked with a solution of copperas or other 
preparation of iron. Generally eight pounds of copperas to 
the barrel of water is used, the barrel holding usually fifty 
gallons. 

The staining and blacking is usually done with the Batchelder 
Blacking Machine, shown in Figs. 73 to 82. 

This blacking is for satin oil, glove grain, plow grain, oil 
grain and dongola. Imitation goat requires a weaker solution, 
about five pounds copperas to the barrel of water being suf- 
ficient. 

Satin oil, after being blacked, is hung up until the blacking 
dries in ; take down, soft board, trim and roll, then give two 
coats of Victor No. 50 and Oil Finish Mixed y 2 and y?. When 
most dry, roll and give another coat of same finish, then roll. 
Always roll while finish is a little moist. Leather treated as 



GRAIN AND SPLIT LEATHER. 425 

above will come out with a strong black color and a dull face 
finish, well filled and a nice smooth feel. 

Bright glove grain, after being blacked, is taken down and 
rolled with a smooth roller in a Combs or Freeman jack, 
and then hung up over night and taken down next morning, 
trimmed and pasted ; reduce paste with Victor Finish No. 
30, this softens paste and gives a strong color. When dry 
stake and roll, then give two or three coats of Victor Glove 
Finish, and when dry roll ; always let each coat dry before 
applying another, have one man put on and another follow 
with fine sponge to streak off. This gives you a very bright 
and black water-proof finish. Leather will be well filled and 
have a nice soft feel, and it is then ready for market. 

Imitation of goat or pebble grain is finished as follows : 
after blacking take and size the sides with one coat of sizing, 
hang up for five minutes until dry, and pebble it by machine, 
grain it four ways, straight and across, then angle it two ways, 
give the side a coat of Victor No. 4 finish, hang up all night, 
and the next morning stake or soft board and grain two ways, 
give another coat of Victor No. 4 finish, run it through polish- 
ing wheel, grain it two ways, oil it with hot paraffin oil, and it 
is finished ready for market. 

Kangaroo chrome tannage, is finished as follows : after 
scouring, black it while wet, when blacked strike out on flesh, 
turn it over and slick on grain side, give a heavy coat of fish 
oil, hang up till dry, then trim it and stake it, soft board it, 
roll or glass, then the sides are ironed with hot irons, such as 
are used in any laundry, and it is finished with two coats of 
Victor dull finish, and it is ready for market. 

Crimping splits are provided from the portion of the hide 
after the grain is split oft", and are finished on the grain side. 
They weigh from 4 lbs. to 8 lbs. 

The splits are put back in the liquors of io° strength for 10 
days to 15 days, and from the liquors they are hung up till dry, 
then taken down and dampened and left to equalize for 24 
hours, stuffed with grease, composed of 25 per cent, degras, 50 



426 THE MANUFACTURE OF LEATHER. 

per cent, hard or brown grease, and 25 per cent, of wax; they 
are stuffed 35 per cent, of their wet weight. The stuffing is 
done in a drum, heated to 165 F., and stuffing is heated to 
140 F. The splits are then set out and hung up till dry. 
They are then taken down and piled full length for about one 
week on the floor, then they are cut over on flesh side and are 
then whitened by machinery on the grain side. One machine 
does both the cutting over and whitening, and will do about 
300 splits per day of 10 hours. 

Then the splits are pasted on flesh side with Batchelder 
blacking machine, and then glassed over the paste with a glass- 
ing machine ; then they are blacked with lamp-black blacking 
on the grain side and glassed while wet; they are then pasted 
over the blacking and glassed again with a glassing-jack ; they 
are then hung up all night, and taken down next morning and 
trimmed, glassed on both sides with glassing-jack ; then they 
are finished with a solution of gum tragacanth, mixed with y^ 
paste and ^3 gum tragacanth solution. This solution is made 
by placing 8 pounds of gum tragacanth in 8 gallons of water, 
and then adding water each day until it has come to the de- 
sired consistency. The solution is thoroughly stirred two or 
three times each day; then add 4 quarts of Irish moss solution. 
The solution of Irish moss is made by taking 10 pounds of 
Irish moss to one barrel of water and boiling for y 2 hour. 
Then add one quart of cod oil, which completes the finish for 
wax crimping splits. 

GUM TRAGACANTH FINISH. 

To make 10 gallons of finish, take four pounds gum traga- 
canth and one quart of cod oil, and dissolve them together 
over night. Next morning pour three gallons of water at the 
boiling point on the mixture. Leave alone for four hours. 
Then stir well, and next day add four more gallons of boiling 
water. Stir occasionally and add two more gallons of boiling 
water a few days afterwards. If too heavy, add more hot 
water, and the mixture will then be ready for use. The cod 



GRAIN AND SPLIT LEATHER. 427 

oil will take the dry tendency from the gum, and when applied 
to the leather will give a fine moist feel. If made as directed, 
this mixture will remain good and ready for use for five years. 
It is specially valuable for shoe shops. It will be found that 
the method here given for dissolving the gum is much better 
than when only water is employed. If water is hard, add a 
little borax. 

PASTE FOR UPPER SPLITS AND CALFSKINS. 

Mix seven pounds flour; seven ounces dry rosin ; one gill 
ammonia ; twenty ounces soap ; two pounds white glue ; six 
pounds tallow. 

This paste, when applied in connection with the above prep- 
aration of tragacanth, should be used in the proportion of 
three-quarters of it to one-quarter of the prepared tragacanth. 
It will make a fine finish that will not peel or crack off. If the 
leather is open, use a trifle more paste to fill up. 

BLACKING FOR SPLITS. 

18 pounds of Babbit soap ; 10 pound barrel lamp-black; 50 
gallons of water. 

Pyrolignous acid black is the best black to use for fine work. 

PASTE FOR WAX STOCK. 

Will make about a ten gallon keg: Five quarts flour, 10 
ounces tallow cake, 4 ounces rosin, 6 ounces beeswax, 18 
ounces soap. 

This makes a nice filler and gives fine feel to leather. Will 
not peel off. Don't put the soap in until the other materials 
have been cooking one-half hour. Then add the soap, having 
previously cut it up fine, and stir till it is thoroughly dissolved. 
The ingredients will readily dissolve and the paste be ready for 
use, one hour after being made. Stir well when cooking. 

IMITATION SEAL AND HOG. 

Imitation seal and imitation hog are printed with rollers, 
which imitate the grains of those skins and are finished as is 



428 THE MANUFACTURE OF LEATHER. 

bright grain. An embossing machine should be used in prefer- 
ence to a pebble for producing these grains. 

PLOW GRAIN. 

Plow grain is made from 40 to 50 pound hides, split in 
two in the hair. They are soaked and limed in the usual 
way. They are unhaired and fleshed by machinery, after 
which they are bated in a bate of chicken manure, 1 ]/ 2 barrels 
to 60 hides, in an England wheel. The bate is steam heated 
to 90 F., and is run for three hours, or until, in the judgment 
of the tanner, the sides are run down low enough. After being 
bated they are washed in a drum with clean warm water; the 
water is heated by a jet of steam to about ioo° F. Then they 
are taken to the tanyard and hung on sticks in a weak liquor 
of about 5 Barkometer. Next day this liquor is pumped off 
and thrown away. The liquor is then renewed each day for 
10 days, being gradually increased in strength up to 10 or 12 
Barkometer. At the end of this time they are taken off the 
sticks and laid away in liquor of 18 Barkometer for 7 days, 
at the end of which time they are taken up and given a second 
layer of 20 Barkometer, where they remain for 8 days longer. 
They are then taken up again and should lay on top of the 
vats for 2 or 3 days, when they are ready to sammy (or semi- 
dry) for splitting machine. In cramped quarters, when it is 
not possible to sammy the sides properly, a power press can 
be used. The leather is next jacked on a stoning jack to take 
out the wrinkles, and is next skived on a belt-knife machine, 
and is next split to 7 or 7^ ounces to the foot thickness, and 
then shaved. The leather is then again sammied and dampened 
for stuffing, which is done in a wheel heated to 160 F., and 
the grease is heated to 140 F. The stuffing is 45 to 50 per 
cent, of the dry weight of the leather, and is composed of 60 
per cent, hard brown grease, 20 per cent, stearine, and 20 per 
cent. English degras. 

The leather is then set out either by machine or hand, and 
hung to dry, and when dry, which usually requires three days, 



GRAIN AND SPLIT LEATHER. 429 

is taken down and snuffed with a buffing slicker. The leather 
is then stained and blacked in the usual way, and is then 
pebbled with a boot grain print, and boarded on the grain 
three ways, angled two ways and across from back to belly. 
The leather is then given a coat of heavy oil, composed of one 
gallon paraffin oil and two pounds degras, and hung up to dry 
over night. In the morning it is boarded again three ways on 
the grain the same as before, and is then soft boarded and 
given a light coat of oil. The oil is composed of one gallon 
of paraffin oil and one pound of degras. It is then hung up 
until the oil strikes in, and then taken down and given a coat 
of finish, the usual satin finish. 

FLESH SPLITS. 

Flesh splits are splits which are finished on the flesh side. 
The usual weight of the flesh splits is from \y 2 to 3^ pounds. 
The splits are taken from the splitting machine, and shaved on 
the flesh side, and any large, loose veins should be entirely 
shaved out. The small, close veins should be merely split in 
the shaving. After shaving, the splits should be run through 
the splitting machine and leveled from the grain side. They 
should then be sammied and dampened ready for stuffing, 
which is 55 per cent, of their dry weight. 

The stuffing should be composed of the following greases : 
70 pounds Brown grease ; 20 pounds English degras ; 20 
pounds refined paraffin wax. 

This is for 170 lbs. of dry splits. The drum is heated to 
160 F. and the stuffing to 140 F. The splits should be run 
in the stuffing wheel for thirty minutes, after which they should 
be taken out and hung up to cool for about thirty minutes, then 
taken down and placed in a pile opened out flat, and allowed to 
remain in the pile until the next day. They should then be set 
out on both sides by machine or hand, and hung up to dry which 
would require about three days. The splits should then be taken 
down and piled lengthwise on the floor and allowed to remain 
for about a week in piles. They are then ready for whitening, 



430 THE MANUFACTURE OF LEATHER. 

which is done by hand with a whitening slicker. The veins 
should be cut out the same as a calf skin, and they should then 
be cut over lightly on the back and given a coat of paste on 
the back; the paste should be mixed with quercitron extract, 
and hung up to dry. They are then glassed by machine on the 
pasted side and then blacked on the flesh side and glassed out 
by machine, after which they are pasted on the black and hung 
up and dried out. 

The splits are then glassed out of paste by machine and 
given a coat of oil if necessary, and are then given a coat of 
gum for a finish. 

The finish coat should consist of jA> paste and y^ of dissolved 
gum tragacanth. 

Oil grain is finished the same as plow grain, only it is a 
lighter leather, 5 or 6 ounces to the foot, and has a smaller 
pebble. 

The bright finish for glove grain is composed as follows for 100 
gallons: 10 lbs. borax to 12 gallons of water. The borax is 
boiled thoroughly in a kettle or tank with steam for ]/ 2 hour, or 
until borax is thoroughly dissolved. Then 50 lbs. of " Gernet 
Diamond C " shellac is thrown into the borax water, stirred thor- 
oughly, and boiled till the shellac is all dissolved, which re- 
quires about 1 hour. Then take 75 lbs. of logwood chips and 
place them in a second kettle and pour over them 75 gallons of 
water and boil t hour with steam. 

If a blue-black color is desired, dissolve x / 2 ounce of bi- 
chromate of potash to every 2 lbs. of logwood used and add it 
to the logwood liquor. 

The logwood liquor is then poured into the shellac solution ; 
both the shellac solution and the logwood solution must be at 
boiling point. The two solutions should be thoroughly stirred 
for 15 or 20 minutes, and then left for 24 hours until cold. 
Then take 25 lbs. of blood albumen and pour over it 5 gallons 
of water and allow it to soak for 10 hours, then stir well and 
pour it into the logwood and shellac solution, stir well and then 
add 21 gallons of beef blood under constant stirring. Then add 



GRAIN AND SPLIT LEATHER. 43 1 

2 gallons of ammonia, stirring well, then put in 2 ounces of 
carbolic acid to prevent the blood from smelling. The quan- 
tity of ammonia is not fixed, as some leather will take more 
ammonia than others — in such cases the ammonia is added at 
the finishing shops. This finish is put on the leather by two 
men, one putting it on and the other striking it off after him. 
They both use fine, soft sponges. They give the leather two 
to three coats in addition to the paste, and it is hung up to dry 
for y 2 hour after each coat. 

Satin oil leather is finished as follows : It is made by putting 
on the leather one coat of bright glove finish, then take four 
quarts of the gum tragacanth solution, one pint of flour paste, 
one and one-half pints of cod oil, one and one-half pints of de- 
gras, then strain well with sieve or cheese cloth and put on the 
leather one coat of this mixture over the bright glove finish. 
This finish is put on in the same way as the bright glove finish. 

Imitation of goat or pebble grain finish is made as follows : 
Four quarts of Irish moss solution, four quarts of flaxseed 
solution, four quarts of solution of sumac, six quarts of beef 
blood, add one gill of ammonia. Two coats of this solution 
are put on. 

Kangaroo finish is made as follows : Sixteen gallons of log- 
wood solution (prepared as in bright glove finish), fourteen 
gallons of beef blood and ten pounds of blood albumen (soaked 
as in bright glove finish), fifteen gallons of gum tragacanth 
solution (as in bright glove finish), then add one ounce of car- 
bolic acid. Two coats are put on. This is for chrome or bark 
tanned stock. 

Very bright pebble grain finish, soft and greasy feel : Blood 
albumen, one pound ; water, one-half gallon. Soak over night 
cold, then add one-half gallon luke-warm water, stirring thor- 
oughly. Strain through a cheese cloth. Then take one gallon 
of blue-black liquor and stir into it, and then take one-half gill 
glycerine, one-half gill of ammonia, mix thoroughly and stir 
into the above. 



432 THE MANUFACTURE OF LEATHER. 

If you wish to obtain the most satisfactory results never 
attempt to make your own finish, as there are manufacturers 
who make a specialty of finish who can always serve you at a 
low price, and often give you valuable information in regard to 
stuffing and finishing the various kinds of leather. 

BLUE-BLACK LIQUOR FOR FINISHES. 

Two pounds best logwood chips, one-half ounce bichromate 
potash, one gallon water. 

BUFFED LEATHER. 

After the leather has been scoured, either by hand or 
machinery, it is pressed dry enough to set, after which it is " set 
out" on the grain side with a stone so as to make it solid, and 
free it from the grain, and it is then stuffed. This variety of 
leather is usually stuffed in the wheel, but is often stuffed by 
hand, and it is performed by laying the side of leather on a 
table, flesh side up, and working over it with a steel slicker, 
after which a preparation of fish oil and tallow is applied with a 
brush to the flesh side. The sides are then hung up in the loft 
to dry, being placed on sticks in tiers, and in this manner they 
remain until dry. 

The superfluous grease is then removed from the flesh side by 
means of a slicker; but sometimes this operation is performed 
by a machine, which is called by the curriers a "grease jack." 

The leather is now in condition for buffing, which is per- 
formed by placing the side on a slanting table covered with 
leather, and removing the grain by means of a whitening or 
buffing slicker. One man will buff from fifty to seventy sides 
of leather per day, the number varying with the condition of 
the leather and the skill of the workman, or the buffing can be 
done by machinery. In order to improve the appearance of 
the edges, the sides after being buffed are next trimmed around 
with a common shoe knife. 

They are then placed on a flat table, fifty sides being piled 
one on top of another with the grain up, and the batch is then 



GRAIN AND SPLIT LEATHER. 433 

blackened with a composition of logwood, water and sal soda, 
which is rubbed into the leather with an ordinary blacking 
brush, or the sides may be blackened by machinery. 

After the pack has been thus treated the sides are then 
blackened with another compound of copperas water or other 
iron preparation. 

The sides are then replaced upon the table, and are then 
" smutted," which operation is performed usually by working 
over the blacking with a woolen cloth in order to remove dirt 
and sediment, and improve the appearance of the blacking. 

The leather is next glassed in order to make it " fine," and 
remove all the creases, and when the glassing is done by hand 
the side is placed on a table and the blacked portion worked 
over with a glass slicker. The sides are then hung up in the 
finishing room for a short time, and then " pasted," which is 
an application of flour paste over the blacking, and commonly 
put on by means of a sponge. After being thoroughly dried, 
the sides are "soft-boarded" by working them with the flesh 
side up, and one man will soften about ioo sides per day. 

The leather is then laid upon the table and slicked off clean 
on the flesh side, and then immediately glassed on the grain 
side, after which it is gummed with a preparation of gum tra- 
gacanth, made of about the consistency of jelly, and applied 
over the paste. 

The sides, after being hung up and dried, are then assorted, 
marked and bundled, and the buffed leather is ready for market. 

FLEXIBLE SPLITS. 

After splits are sorted at the belt knife machine, take them 
to the drum wheel. Then dissolve half a bale (a bale weighs 
about 250 pounds) of gambier, or the same proportion of ex- 
tract, in a barrel of water, so that the liquor will stand at 80 
degrees barkometer. Now bring this liquor down to 25 de- 
grees by adding six pails of sweet liquor, 12 degrees barko- 
meter. Put the solution in the mill, and let the splits follow. 
Close judgment must be used here. If the splits are large, mill 
28 



434 THE MANUFACTURE OF LEATHER. 

for 45 minutes. Remove and leave in piles for say 12 hours. 
Then throw them into a vat containing 20 to 25-degree liquor, 
and leave until well-tanned, say three or four days. 

Take splits out and put in wash-wheel with plenty of luke- 
warm water through the axle of the wheel. Have plugs in 
wheel so that impurities may be washed out. The wheeling 
should occupy 20 to 30 minutes. Now take 50 gallons of 
water, to which add four pails sumac (about 20 pounds of 
sumac to a pail), and one pound of alum. Cook to the boil- 
ing point. Then let cool to no° F. The splits mean- 
while are still in the wheel, and to them should be added from 
four to six pails of the sumac liquor just made, and the wheel 
run for about 30 minutes at 16 revolutions per minute. Re- 
move and rinse leather in clear running water. 

Now heat 50 gallons of water to 120 F., into which put 
two quarts of sugar of lead. In another barrel of water con- 
taining 50 gallons, put one quart of vitriol. Immerse splits 
first in sugar of lead solution ; then in vitriol solution ; then in 
clear, running water. The leather is now ready to be sammied 
in the usual way like satin or wax splits. 

After this is accomplished and the leather ready to set, it 
should be put under a setting-machine and well set, and then 
rolled down fine and soft. For setting, the splits should be as 
dry as possible. For instance, 100 pounds dry splits should 
not have over 35 pounds water after they are set by jack or 
hand. Now make the following: Three pounds Irish moss and 
one-half pound soap, and cook with three gallons of water and 
strain. The mixture, if properly attended to, will resemble a 
heavy cream. Set this on one side and apply a coat of it 
liberally to both sides of the splits. Then hang up in a warm 
room. When dry take down and leave in a pile to press for a 
day or so. Now prepare the following: Three pounds Irish 
moss, one-half pound chip soap, half pound starch. Dissolve 
this in cold water, say four gallons, and cook well. The re- 
sult should be a heavy substance. 

Take splits to jack. Have one man at jack and one man to 



GRAIN AND SPLIT LEATHER. 435 

apply the mixture to flesh side first, taking the splits one at a 
time, giving liberal dose to the flesh side, same time running 
through the jack in wet condition. Be sure and keep one split 
ahead of the machine. Hang up to dry them, take down and 
go over grain side same as flesh. The leather is now finished, 
and is ready to be measured and bundled for the market. 

Degras. — Where we speak of degras in this chapter we, of 
course, mean that which is obtained in England and Germany 
from wool grease, not the French degras which is obtained 
from the oxidation of fish oil used in the tannage of chamois 
leather. 



CHAPTER XXIX. 

ENAMELED LEATHER, PATENT LEATHER, FURNITURE OR UP- 
HOLSTERING LEATHER, REGALIA LEATHER. 

| 

Enameled leather is grained or pebbled so as to give it a 

broken surface. Patent leather has a smooth glossy surface. 

The steer hides employed for the production of enameled 
and patent leather to be used for carriage tops, and also those 
employed for furniture or upholstering leathers, are the largest 
and finest slaughter hides that can be obtained, practically 
free from blemishes. The largest and best hides are selected 
from those which are purchased in the markets of Chicago, 
Kansas City, St. Louis and Omaha. Hides which measure 
six feet eight inches across the brisket and over are taken. 
Cow hides which measure six feet four inches across the 
brisket and over are taken for trimmings and furniture 
leathers. Large bull hides, measuring six feet four inches 
across the brisket, are used for patent collar leather, and 
smaller size for shoe tippings. 

Sometimes during a scarcity of hides they are imported 
from France, Germany, Switzerland and other countries, and 
Anglo-American hides are brought from England ; the latter 
hides being those of animals which have been exported from 
America to England and slaughtered there. 

The soaking, unhairing and fleshing of the hides is the same 
as has been described for other varieties of leather. The lim- 
ing is longer, usually for ten days. If the limes are heated, as 
some tanners employ them, they remain for a shorter time, 
and are then struck on the beam to work out the lime. Then 
they go into the bate of pigeon or hen manure, which by some 
tanners is heated to about ioo° F., where they remain for five 

T436) 



ENAMELED LEATHER, ETC. 437 

or six hours, care being observed to handle them up five or six 
times during this period. Some tanners use a cold bate, in 
which the hides are allowed to remain for about twenty-four 
hours. They then go on the beam and are worked over very 
carefully with a bate stone. When they have been properly 
worked with the bate stone and while they are still on the 
beam, they are further worked with a steel worker in order to 
free the hides from lime and dirt as much as is possible. They 
are then placed in a perforated wash wheel and washed. The 
wash wheel is put in motion and a two-inch stream of cold 
water run continuously on the hides until the water coming 
from the wheel shows no signs of lime. The time consumed 
in this washing varies, and depends upon the quantity of lime 
and dirt which is in the hides when they are thrown into the 
wheel. Hides treated in this manner will go into the liquors, 
practically speaking, perfectly free from lime and grit, which 
will prepare them better for splitting as the sand and dirt 
which may have been collected in the flesh will have been re- 
moved by the washing in the wheel. This washing may be 
done in two or three minutes, or the time required may be 
longer, depending upon circumstances. As soon as the water 
runs clear from the wheel, the washing is complete and the 
motion of the wheel should be stopped. This washing is a 
very important step in the manufacture of enameled or patent 
leather, or of any other grade of leather, as hides treated in 
this way do not carry any lime or dirt into the liquors, and the 
liquors thereby become more effective. If this washing is not 
done, it will be necessary to place the hides in a weak sour 
liquor containing almost no tannin, so as to neutralize the lime 
that may be left in the hide. 

Care should be taken not to allow the wash wheel to run for 
too long a time, as it would result in making a loose and 
spongy flank. 

After they have been properly washed the hides are in con- 
dition to go into the "handlers" or "rockers" to be properly 
swelled for the reception of the tanning liquor. 



438 



THE MANUFACTURE OF LEATHER. 



The tanning vats used in some tanneries are shown in Fig. 1 16. 

The material employed by some tanners for tanning the 
hides is a mixture of oak and hemlock bark, making what is 
known as " union tannage." Some tanners use vats having a 
circular bottom, and above which there is placed a revolving 
wheel which agitates both the tanning liquor and the hides ; 

Fig. ii 6. 




TANNING VATS IN PATENT LEATHER FACTORY. 



there being usually a number of these vats placed in a line, as 
shown in Fig. 116. The wheels are worked for about fifteen 
minutes in each hour. Other tanners use "rockers" where 
the hides are stretched out and hung on hooks, the hides being 
rocked three or four times a day. They remain in the rockers 
for about twelve days, the time depending upon the strength of 
the liquor, etc., the longer they hang the plumper and firmer 
the leather will be. They are then taken out and put in a large 



ENAMELED LEATHER, ETC. 439 

power press, and the surplus liquor pressed out. They are then 
hung up and partially dried or " sammied " to prepare them 
for the splitting machines. These machines are known as the 
"Belt Knife" and "Union." 

When the hides are in proper condition they are split from 
three to four times, three times being the average, ist, the 
buffing is taken off, which is used for hat sweats, pocket books, 
book bindings, etc. 2d, shoe tippings, upholstering leather, 
carriage tops, etc. 3d, comes the middle split, which is used 
for soft dash or hard dash, and if a very heavy hide, a flat 
split or "junior winker" used by harness makers, is taken; 
fancy splits, enamel splits, inner sole, bag leather, shoe splits, 
collar leather and for various other purposes. 4th, comes a 
slab which is used by trunk makers and collar makers. If it is 
very light, it can only be used by trunk makers ; if heavy, by 
collar makers. 5th splits are very rare, unless the people are 
making very light splits, and light splits as a rule have very 
little strength on account of having very little fibre. 

The hides and splits after leaving the splitting machines are 
re tanned in japonica, gambier, hemlock, quebracho, canaigre, 
etc., as circumstances demand. They remain in the re-tanning 
process from about three to ten days, the time varying in differ- 
ent tanneries, depending upon whether the tanner uses warm 
or cold liquors and how well the hides are tanned before split- 
ting. The tanner may sometimes be rushed with his " hand- 
lers " or " rockers," thus forcing the hides to be split in a 
greener state. In such cases it will be necessary to give the 
hides a longer time in the re -tanning. About three days for hides 
and about ten days for splits is the usual time in cold liquors, de- 
pending upon the kind of leather which it is desired to produce. 
Warm liquors run from 95 ° to ioo° F., cold liquors from 75 ° F. 
down. The re-tanning is done in boxes which measure seven 
feet and six inches long, by five feet wide, by three feet six 
inches deep inside. There are trays set over the boxes on one 
side to hold the hides and splits as they are handled out of the 
liquor each day. 



440 THE MANUFACTURE OF LEATHER. 

The heavy leathers, such as flap, etc., require longer time, 
say about fifty days, and are twice laid away, the first layer 
being for about twenty-four days, and the second for about 
twenty-six days. This treatment, however, is arbitrary. The 
hides remain in the last layer until wanted, it may be for three 
or six months, depending upon the demand for the leather. 
It is a good place to preserve the hides if the tanner has plenty 
of spare vats and little storage room. 

Then the hides and splits are placed in sumac liquor and re- 
main for one day ; about one-half pound of sumac being used for 
each hide. The amount of sumac employed varies, however, 
with the practice in various tanneries. Some tanners use a re- 
fined extract of sumac which takes the place of the ground 
sumac leaves, saving the tanners the time of leaching, also sav- 
ing the loss that often occurs from souring liquors. 

The hides and splits are next scoured by hand on a table, 
which accomplishes two things, i. e., ist, the removal of the ex- 
cess of tanning material, dirt, etc. ; 2d, the setting out. Then 
they are stuffed with various mixtures of cod oil, degras, linseed 
oil, etc. It is dangerous to use either cod oil or degras unless 
a strictly purer article can be had, as a poor quality of cod oil 
or degras made from it will cause the leather to gum on the 
surface and to stick together and stain in spots. If there be 
any question about the quality of the cod oil and degras, it 
will be better to use only either raw or boiled linseed oil. 

A stuffing which has been found to be very satisfactory in 
practice is made as follows : 

Dry white lead 30 pounds. 

Litharge . . 30 pounds. 

Raw linseed oil 50 gallons. 

The dry white lead and litharge are each mixed with about 
ten gallons of raw linseed oil, and these two mixtures of twenty 
gallons are poured into the kettle and thoroughly stirred be- 
fore it goes upon the fire. The stirring is done with the idea 
of preventing the white lead and litharge from settling in the 



ENAMELED LEATHER, ETC. 44 1 

bottom of the kettle. This mixture of white lead, litharge and 
linseed oil is boiled together for six or eight hours and carried 
to about 400 F., or until it is reduced to the consistency 
of syrup. The mixture when cold is reduced with naphtha, 
say fifty gallons of naphtha to fifty gallons of oil, or it can be 
reduced to any required body and applied to the hides or splits. 

After they come from the scouring and stuffing tables, the 
pieces, hides, splits and buffings are tacked on stretching frames 
and stretched, and allowed to become thoroughly dry. 

A good frame for stretching leather is shown in Figs. 117 to 
121, and is the invention of Charles P. Oliver and Theodore 
P. Howell, of Newark, N. J. 

This device possesses the merit of unusual simplicity and 
cheapness of construction, and also is susceptible of operation 
without removing the frame from its pendent position from the 
supporting-bars. 

Fig. 117 is a representation of a top view of Oliver and 
Howell's Machine. Fig. 1 18 is a vertical transverse section of 
the same. Figs. 119, 120 and 121 are details of the same. 

A represents the upper and B the lower cross-bar of the 
stretching-frame, and C indicates the sides. On the front sides 
of the bar C, or upon the sides of such bars, are affixed per- 
forated plates, marked a. These perforated plates are adapted 
for use upon wooden upright bars ; but in case such bars be 
made of metal, the plates may be dispensed with, and the 
cross-bars themselves be perforated. The cross-bar A is con- 
structed with a rounded upper surface, to adapt it for holding 
the centre of the hide, inasmuch as this apparatus is designed 
for attaching both flanks or sides of the hide to the sliding bar 
D. The letter D represents the sliding or stretching bar, 
which is arranged with reference to the bars A and C in the 
manner shown. The letter c indicates the short arm of a joint 
attached to the sliding bar D, and / indicates the long arm 
thereof attached to the bar B, each connection being made 
with a suitable pivot-pin or hinge. These two arms of the 
joint are united by a tongue-and-groov.e joint, as shown in Fig. 



442 



THE MANUFACTURE OF LEATHER. 



1 1 8. It will be observed that the end of the sliding bar D is 
slotted to provide for holding the forearm of the joint and allow 
the movements thereof. The letter y indicates a quadrangular 



im\ \ : 



S3 



■■# 



Fig. 117. 



Cf 



I «-.-.=::.. I 



[,:"".-.••:] 



2 



Fig. 118. 



Fig. 119. 




@= 



Fig. I2i. 
■» — 



h'^*« 



I 



Fig. 120. 



I . 



wrist firmly attached to the short arm of the joint. It is pre- 
ferable to cast this arm and wrist in one piece of metal. The 
letter H represents a wrench, the head of which is adapted to 
fit upon the wrist y. 



ENAMELED LEATHER, ETC. 443 

To operate this device, tack the moist hide to the sides of 
bar D, allowing the centre thereof to rest upon the oval upper 
surface of bar A, and place the wrench head upon the wrist y. 
Then turn the wrench downward, bringing the two arms of the 
joint toward or beyond a right angle, thereby increasing the 
distance between the bars A and D. When the skin is suffi- 
ciently stretched, place a pin above the bar D in one of the 
apertures of the perforated plate, and permit the skin to dry, or 
be manipulated, as the operator may see fit. 

The dry room is heated by steam and a ventilating fan draws 
off the moisture ; the drying usually requiring two or three days. 
The hides and splits are then taken from the stretching frame 
and are passed through a pin-block machine, to give them a 
preliminary softening, and are next taken to the table and 
boarded by hand to complete the softening. The softening 
table is covered with a split, which is tacked on in the wet state 
so as to dry even and taut. 

After the hides, splits and buffings are softened they go to 
the " patcher," whose business it is to patch up the pieces by 
the putting on of a patch with glue to prevent the enamel com- 
position which is later on to be applied from running through 
and staining the under-side of the piece. Then the hides, splits 
and buffings go to the table of the sorter, who classifies them 
into the different grades as to quality, size and substance. The 
buffings are graded as to the degree of imperfections, such as 
horn scratches, rough grain brands, grub holes, salt stains and 
substance, making about five selections. The buffings are 
further graded as to the manner in which they split, viz., the 
" Belt Knife " and " Union." The " Belt-Knife " buffings have 
the head and butt on them. The "Union" buffings have 
either the head or butt missing. The hides are divided into 
two classes, hand-buffed and machine-buffed. The hand-buffed 
hides bring the best price, as the buffing is sacrificed and only 
the best hides are selected for this class. 

The hand-buffed hides make the following grades, viz. : grain 
dash, landau, calache, top hides, upholstering, trimming, shoe 
enamel, shoe tipping and binding leather. 



444 THE MANUFACTURE OF LEATHER. 

The machine-buffed hides make the following grades, viz. : 
grain dash, top hides, upholstering, trimming and binding 
leather. 

The splits make the following kinds of leather, viz. : skirting, 
hard dash, soft dash, black and fancy enameled splits. 

The buffings which have been selected for japanning are di- 
vided into three classes ; the best grade going into enameled 
buffings, the next grade into fancy colored buffings, and the 
last grade into patent or black buffings. The buffings which 
are not required for japanning are sold in the russet for mak- 
ing stained buffings, which are used for book bindings, pocket- 
books, ladies' hand-bags, etc. 

The hides, splits and buffings which have been selected for 
enameling are next toggled, stretched and tacked on a frame 
with ten-ounce tacks. The hide frames are about nine feet by 
ten and one-half feet outside measurements, and are made of 
seven-eighths inch stuff, four and one-half inches wide. The 
split frames are about nine by nine feet, made of the same 
material. For japanning side leather the frames are about four 
and one-half feet by nine feet, made of one and one-quarter 
inch stuff, five inches wide. 

BLACK ENAMELED TOP LEATHER SUCH AS IS USED FOR BUGGY AND CAR- 
RIAGE TOPS. 

The hides next receive a heavy coat of daub, which is made 
of raw linseed oil boiled to a jelly. The boiling usually re- 
quires about twenty-four hours, which time includes about five 
hours allowed for the addition of naphtha, which is hereafter 
described. The time is usually spread over two days, twelve 
hours being consumed each day. The kettle in which the oil 
is boiled should be twice the capacity of the oil to be boiled at 
one time. The kettle should be portable and mounted upon a 
truck, so as to wheel it off the fire when the temperature be- 
comes too high. There should be a lug or flange for holding 
thermometer in kettle. The boiling is done over a coke fire 
similar to the fires in use in an ordinary varnish factory. The 



ENAMELED LEATHER, ETC. 445 

oil is continually stirred from start to finish with an iron paddle 
about eight feet long, or of any suitable size, with holes made 
through the paddle portion, which is about three-sixteenths of 
an inch thick, to prevent the throwing of the oil out of the 
kettle. 

The oil is carried gradually to about 580 F. the first twelve 
hours, and is then lowered to about 400 F. before leaving 
work for the day. The next day the temperature of the oil is 
again gradually increased to from 580 F. to 6io° F., depend- 
ing upon the nature of the oil, the weather, etc. Some oils 
will cook with less heat than others. When the oil is cooked 
to the consistency of a jelly on the second day, it is taken off 
the fire and cooled down to about 400 F., and naphtha is 
added in the proportion of one and one-third gallons of naphtha 
to the gallon of oil. Say we are boiling seventy-five gallons of 
oil and it is ready to receive the naphtha ; the naphtha is added, 
twenty-five gallons, to reduce the temperature of the oil, which 
is slowly stirred in, and when this twenty-five gallons has dis- 
appeared, twenty-five gallons more of naphtha are added, under 
constant stirring, so as to break up the composition and allow 
the naphtha to penetrate it, and this is continued until about 
one hundred gallons of naphtha are added, only twenty-five gal- 
lons at a time being put in. The more rapidly the naphtha is 
added and the composition stirred, the better. The fire used 
for cooking the oil must be put out, every spark of it, before 
the naphtha is added. The brick-work of the furnace is flooded 
with water, so as to prevent the gas which comes from the 
naphtha from striking the hot bricks and thereby causing an 
explosion of all the naphtha. When you desire to make a 
foundation for a dark color, such as black enamel, soft dash, 
hard dash and black buffings, add one pound of lamp-black 
of the best quality free from grease to four gallons of the 
composition just described, which is known technically as 
"sweet-meats." It does not take the name of daub until the 
lamp-black is put in. 

The lamp-black is added under constant stirring. In large 



446 THE MANUFACTURE OF LEATHER. 

works, such as the American Oak Leather Company of Cincin- 
nati, Ohio, the stirring is done in a mill built for the purpose, 
which holds about sixty gallons. It has two upright pieces of 
iron or blades bolted to the bottom and extending to the top of 
the mill. The dasher which revolves at the top of the mill has 
four blades bolted to it on one side and two blades on the other, 
so arranged that the upright blades pass between the revolving 
blades. The mill has an opening at the bottom through which 
the daub is drawn. The mill is driven by power and makes 
about sixty revolutions a minute. The daub is ready to apply 
to the leather as soon as it comes from the mill. This daub is 
applied to the hide as a filler and is put on with a steel slicker, 
the blade of which measures ten and one-half inches long by 
two and five-eighths inches deep, and nearly one-eighth of an 
inch thick, having rounded corners and a knitting-needle edge. 
The daub must be worked in thoroughly and the excess scraped 
off with a slicker, care being observed in the scraping not to 
scratch the hide. The hide is then exposed to the sunshine or 
air until the daub coat is thoroughly dry. When dry the hide 
is given a second coat of the same composition. Usually the 
second coat is put on the next day, and it is then run into the 
oven (see Fig. 122) to dry, remaining from ten to twelve 
hours at a temperature of from no° F. to 120 F. The hide 
then receives a slicker coat, which is linseed oil boiled to about 
the consistency of New Orleans molasses. This slicker coat is 
put on with a smaller and thinner slicker than that used for the 
daub, and is a scant one-sixteenth of an inch in thickness. 
After the slicker coat is dry, which usually requires about 
twelve hours in the oven, it is rubbed with a flat piece of pumice 
stone to make a smooth surface. The hides next receive a 
coat of enameled varnish, which is made of linseed oil and 
Chinese blue, boiled down to the same consistency as the 
slicker varnish. It is boiled for about eight hours, and is grad- 
ually carried to about 560 ° F., being stirred all the time. This 
varnish is reduced with naphtha. After the first coat of varnish 
is put on, the hide is again placed in the oven and thoroughly 



ENAMELED LEATHER, ETC. 



447 



dried, which usually requires about ten hours. It is then taken 
out and pumiced, and receives the final or finishing coat, and is 
again placed in the oven and dried at about 140 F. The hide 
is next exposed to the sun and air to remove the sticky surface. 
The length of exposure varies, running from three to ten hours. 
The hide is then taken from the frame, and hung in a damp 

Fig. 122. 




DRYING OVEN IN PATENT LEATHER FACTORY. 

room for twenty-four hours, and allowed to regain the natural 
moisture lost in the japanning process. The edges are then 
trimmed to remove the tack marks, toggle holes and varnish. 
It is then boarded by hand to raise the grain after which it is 
measured, and is ready for the market. 



SMOOTH FINISHED PATENT LEATHER. 

The split receives three coats of daub. The last coat of 
daub when dry is pumiced. Then it receives a coat of black 



448 THE MANUFACTURE OF LEATHER. 

varnish, which when dry is also pumiced. The second coat of 
black varnish is then put on and dried, and after the drying is 
completed this coat of varnish is again pumiced. The daub 
used for splits is nearly the same as for the hides, but the boil- 
ing of the oil does not require so long a time, about twenty 
hours being sufficient. 

The black varnish is made of linseed oil and raw umber 
boiled from eight to ten hours at a temperature of from 
500 to 580 F. being stirred continually. The cooking is 
known to be done or finished when a sample of the varnish 
taken from the pot and cooled can be stretched into a thread 
between the thumb and first finger. When the varnish is 
boiled to this stage it is taken off the fire and cooled down 
to about 350° F., and lamp-black of the best quality, free 
from grease, is gradually added under careful and continuous 
stirring until it becomes one body. The lamp-black is added 
in the proportion of about one- fourth pound to a gallon of oil, 
measured before boiling. This black varnish is then reduced 
with naphtha until it will flow freely under the brush, usually 
about one and one-fourth gallons of naphtha to one gallon 
of the raw linseed oil measured before boiling. The split next 
receives three coats of finishing varnish as follows : The 
first coat is flowed on with a brush and dried in the oven 
at about 170 F. for from ten to fifteen hour's, or until it is 
thoroughly dry ; care being always observed not to get it 
too dry. It is pumiced and receives the second coat of varnish, 
which is again dried at about 170 F. for ten to fifteen hours, 
the same care being observed as in the first drying. It is then 
very lightly pumiced with a very fine, smooth stone. It is then 
perfectly cleansed of all dirt, dust and grit. The split, in fact, 
receives two cleansings : 1st, the dry dusting, which is done 
with a dry sweep ; 2nd, the cleansing, which is done with a wet 
sweep. 

The split is now ready for the final coat of varnish, which is 
flowed on very carefully, and is then put in the oven and dried 
at a temperature of about 170 F. and remains usually for about 



ENAMELED LEATHER, ETC. 449 

forty-eight hours, judgment being used as to the degree of heat, 
which is intended to bake or unite all the compositions applied 
to one body. The finishing varnish, three coats of which are 
applied, is made of linseed oil and Chinese blue. From two to 
six ounces of Chinese blue is added to the gallon of oil, and 
this is boiled to about the consistency of the black varnish. 
The composition is stirred continually and is boiled for eight 
or ten hours. The composition should cook at 580 F. It 
should then be dipped over into a reducing pan, which must be 
outside of the boiling-room, and is allowed to cool over night. 
The next day it is reduced or thinned with one gallon of naph- 
tha to each gallon of oil. The naphtha is added gradually 
under constant and continual stirring. This varnish is stored 
in a room which has about Jo° F. for its temperature, and re- 
mains for about six weeks before using. After the split has 
been exposed to the heat of the oven for about forty-eight 
hours, it is taken out and cut off the frame, trimmed and meas- 
ured ready for the market. 

PLAIN BLACK BUFFINGS. 

The buffing receives one coat of black daub the same as the 
hide, two coats of black varnish and two coats of finishing var- 
nish. The drying must be done at about one-third less tem- 
perature than for splits. Care should be taken not to dry too 
much. The buffing should be exposed to the sun or air on the 
finishing coat. It is then cut from the frame, trimmed and 
measured ready for the market. 

FURNITURE OR UPHOLSTERING LEATHER. 

The finishing of furniture leather for the first three coats of 

daub is the same as for black enameled top leather previously 

described. Then it is painted of any desired shade. The 

number of coats depends upon the shade required. Furniture 

leather is not varnished. It is dried at about 120 F. The 

colors can either be bought ground in oil or dry, the grinding 

being done under your own supervision and with oil especially 

purchased for the purpose. 
29 



450 THE MANUFACTURE OF LEATHER. 

REGALIA LEATHER. 

Regalia leather is made from about the same selection of 
hides as is the furniture and upholstering leather. The usual 
colors* are red, white, blue, orange, lemon and maroon, but any 
color that is desired can be produced. Regalia leather receives 
the same number of coats as furniture or upholstering leather, 
and is dried in the oven at about the same temperature. But 
this daub has no lamp-black in it ; it is in'fact the " sweet-meats " 
already referred to reduced to the substance of daub. It is 
pumiced on the last daub coat, and it receives as many coats 
of color as are necessary to produce the shade desired. The 
colors are mixed with a fine clear varnish, free from gum ; but 
the last coat is clear varnish. Care should be used to pur- 
chase the very best colors that are made. Buy them dried, and 
grind them in oil yourself. The oil used is what is called the 
clarified boiled linseed oil. We have the formula of a varnish 
which is used for making regalia leather and all delicate colors. 
This varnish is free from gum, and leather coated with it will not 
break or stick. It is the most valuable varnish for the pur- 
pose which we have ever seen. We are not at libeity, how- 
ever, to make public the formula of this varnish, as there are 
other parties interested with us in its ownership. 

NOTES. 

The finishing room should be kept clear of dirt of all kinds. 
There should be no draft. Ventilation should be through the 
roof. No rags and no clothes should be allowed in the room. 
The men when finishing wear no clothes except trousers and 
shoes. 

Naphtha is used as a reducing agent for the compositions 
instead of turpentine, because it is cheaper, costing only about 
one-sixth as much. 

Compositions which are intended to be aged are, however, 
better produced with turpentine, as naphtha will evaporate too 
quickly. 

The thermometer used for boiling the oil can be bought from 



ENAMELED LEATHER, ETC. 45 I 

the Hohmann & Mann Manufacturing Co., Plymouth and Jay- 
Streets, Brooklyn, N. Y. 

The sweep and the round varnish brush used for flowing on 
both the black varnish and the finishing varnish, which is a 
seven-inch Russia bristle, and the flat brush used for painting 
furniture leather, can be purchased from Dixon & Ripple, 
Newark, N. J. The slickers can be bought from Richardson, 
Newark, N. J. H. L. Pope & Co., Dayton, Ohio, make a good 
grade of linseed oil by the old process, which is much used for 
manufacturing enameled and patent leather. 

A GOOD WAY TO OPEN ENAMELED AND PATENT LEATHER WHICH IS STUCK 

TOGETHER. 

Put the leather out on the grass before sunrise, while the dew 
is on the grass. Let it lie until the sun warms it through, and 
then strip it. This method, of course, can only be used in 
warm weather. 

PRESERVING THE GLOSS ON PATENT LEATHER. 

The following is a French recipe for preserving the gloss of 
patent leather : Melt pure wax over a water-bath, place on a 
moderate coal fire, add first some olive oil, then some lard, 
and mix intimately by stirring ; next add some oil of turpen- 
tine, and finally some oil of lavender, fill the resulting paste into 
boxes, where, on solidifying, the necessary consistency will be 
acquired. To restore the gloss to the leather apply a little of 
the paste and rub with a linen rag. This will keep the leather 
soft and prevent cracking. 

RENEWING THE SURFACE OF JAPANNED LEATHER. 

In 1863 Wm. Hoey patented in England the following com- 
pound for renewing the surface of japanned leather: Two 
ounces of paraffin, or rock oil, or a mixture of both in any 
proportion, to which are added one-quarter of a drachm of oil 
of lavender, one-quarter of a drachm of citronel essence, and 
one-half ounce of spirits of ammonia. The mixture is applied 
lightly to the surface of the leather. 



452 THE MANUFACTURE OF LEATHER. 

PREPARING THE CUT SURFACE OF SPLIT LEATHER FOR MANUFACTURING 
JAPANNED OR ENAMELED LEATHER. 

The common way of buffing the hide or preparing it for 
japanning or enameling is either by shaving off the inequalities 
with a currying-knife, or by taking off a light buffing with the 
regular splitting machine. This light buffing, when finished, is 
of little value, bringing from one to three dollars. The way 
japanned or enameled leather is often treated is by applying all 
the coats of the composition to the leather after being tanned, 
and when perfectly dry on the frames. The naphtha or turpen- 
tine in the composition is then absorbed by the dry leather, 
and it becomes dry and harsh ; but by applying the first coat 
of the composition when the leather is wet and the pores are 
filled with tan-ooze, the naphtha or turpentine evaporates be- 
fore the leather becomes dry, and is not absorbed by it, and 
the leather is left soft and flexible and more easily worked. 

If a heavy buffing be taken off, it leaves the surface fibrous 
and coarse, and it is necessary to have a smooth surface to 
finish on — that is, to japan or enamel. 

Stephen J. Patterson, of Bridgeport, Conn., in 1883 patented 
the following method for forming an artificial grain on the hide 
after it has been buffed or split with a regular splitting 
machine. 

This process of treatment applies equally well to light buff- 
ings or splits, but is especially adapted to heavy ones by 
largely increasing their value. 

Patterson's improvement is as follows : When the split hide 
comes from the tan-liquor after the tanning operation is com- 
pleted, it is slicked out on a table and a light coat of oil spread 
over the surface with a sponge or soft brush. Then it is tacked 
on a frame, and while still wet the fibre or nap of the freshly- 
cut surface is brushed down smooth in one direction with a 
flexible bristle brush (like a shoe-blacking brush, but larger), 
which simply gives direction to the fibre or nap ; and then 
there is applied, while the hide is still wet, with the same brush 
or with a sponge, rubbing in the same direction, a coat of com- 



ENAMELED LEATHER, ETC. 453 

position made from linseed oil boiled down to a jelly and re- 
duced with naphtha or turpentine to the proper consistency. 
After this application repeat the brushing operation as before. 
The hide is now left to dry, and when dry the composition 
holds the fibre or nap in place, and the leather has a smooth 
surface to japan or enamel. When dry it is finished the same 
as other japanned or enameled leather. The hide is not 
dubbed with a mixture of cod oil and tallow or other grease, as 
in the ordinary method of preparing heavy leather. For shoes 
and harness only a light coat of oil is applied as stated. It is 
buffed or split with the splitting-machine when about one-third 
tanned. 

For treatment by this process, Mr. Patterson takes off a 
heavy buffing with the largest size improved " Union Splitting- 
Machine," making a buffing about three-fourths the size of the 
hide. This is thick enough to japan for shoe leather or similar 
purposes, and will bring from four to eight dollars when fin- 
ished. The extra expense will not exceed one per cent, of the 
cost of the hide. 

JAPANNED LEATHER IN IMITATION OF ALLIGATOR SKIN. 

The object of this process, which was patented by Franklin 
S. Merritt, of Boston, Mass., in 1 871, is to produce japanned 
leather in imitation of alligator skin. 

The leather is prepared by the ordinary process of currying 
for patent or enameled leather. Afterward it is coated with a 
composition of linseed oil boiled with driers, viz., litharge, burnt 
or raw umber, sugar of lead, sulphate of zinc, Prussian or Chi- 
nese blue, mixed with naphtha, benzine, spirits of turpentine, or 
camphine, with sufficient lamp or ivory-black to give it color- 
ing. 

The leather, after being coated with several layers of the 
composition, each being dried before the next is applied, is 
rubbed with pumice-stone to give a smooth surface to the coat- 
ing. Finally the last layer is applied and dried without rubbing 
with pumice-stone, the whole making, thus far, what is usually 



454 



THE MANUFACTURE OF LEATHER. 



called "patent or enameled leather." The leather in this state 
is next wet sufficiently to soften it to admit of its receiving and 
retaining the impression of the die or rollers. Next the sheet 
of leather is passed between rollers or dies, or compressed by 
the same, so as to emboss it with the required figure or series 
of convexities. Next it should be softened while wet by 
" boarding," or by any other mode of effecting such as usually 
adopted by leather dressers, and then dried. 

Fig. 123. 




Fig. 124. 



Figure 123 represents a face view, and Figure 124 a section 
of a piece of leather made as described. 

When finished it may be used for many purposes in the arts, 
particularly in the manufacture of hand-satchels, shoes, etc. 



LINSEED OIL. 



Linseed oil, which enters so largely into the "sweet-meats," 
and daub for enameled and patent leather, is obtained from 
seeds of Linum usitatissimum (Linn). They contain 30 to 35 
per cent, of oil, 26 per cent, of which can be obtained. 



ENAMELED LEATHER, ETC. 455 

Winter Flax. Spring Flax. 

Oil 35» 2 ° P er cent: - 3i-6o per cent. 

Organic Substance* S3- 00 " 574° " 

Ash 3.15 " 3.20 " 

Water 8.65 " 7.80 " 

100.00 per cent. 100.00 per cent. 

* Protein substance therein .... 22.10 " 24.00 " 

The oil is obtained by either of the three following pro- 
cesses : 

Cold Drawn Oil. — The seeds are crushed, ground or bruised, 
and expressed without heat. This is considered the best oil, 
and in Russia and some parts of Germany is used as a table 
oil and for baking. By this process the seeds yield from 20 to 
21 per cent, of oil. 

Ordinary Linseed Oil. — It is prepared in the same manner 
as above, but with the assistance of heat, which gives it a disa- 
greeable taste. The yield is from 27 to 28 per cent. It is 
used for technical purposes. 

By Extraction.— -With a yield of 32 to 33 per cent. Seeds 
two to six months old are generally used, as the oil expressed 
from fresh seeds is viscous and turbid. The cold-drawn oil is 
golden yellow, and has a peculiar but not disagreeable taste 
and odor. The hot pressed oil is amber-colored or brown- 
yellow, and has an acrid taste, due to traces of volatile fatty 
acids, such as butyric, valerianic and caproic acids. 

Linseed oil is somewhat thickly fluid, and, as it belongs to 
the drying oils, very quickly absorbs oxygen from the air, be- 
comes lighter in color, rancid, finally entirely thickly fluid, and 
dries. Its specific gravity is 0.9375 at 50 F. ; 0.9463 at 
55-5° F. ; 0.9350 at 59 F. ; 0.9325 at 68° F. ; and 0.9300 at 
77° F. At 59 F., the oil is 9.7 times more thickly fluid than 
water; and at 45. 5 ° F., 11.5 times. At a decreasing tempera- 
ture, it becomes gradually thicker, becoming pale and turbid 
with increasing cold, and congeals to a solid yellow mass at 
16. 5 F. At 266 F., it commences to boil, and after boiling 
for some time at 482 ° to 554 F., until it has lost about one- 



456 THE MANUFACTURE OF LEATHER. 

twelfth of its weight, it becomes thicker, viscous and sticky, 
and furnishes varnishes. By heating it still further, until it has 
lost one-sixth of its weight, it becomes still thicker, the product 
being printers' ink. By heating linseed oil to 608 ° to 707 F., 
it ignites and burns quickly without further external heating, 
until tar and carbon remain. By interrupting the burning by 
covering the boiler, there remains a brown, turpentine-like sub- 
stance, the so-called bird lime. Linseed oil is soluble in 1.5 
parts of ether, in forty parts of ninety per cent, spirits of wine, 
in five parts of absolute alcohol. It is miscible in all propor- 
tions with chloroform, oil of turpentine, bisulphide of carbon, 
etc. Its elementary composition is : 

Cold Drawn. Hot Pressed. 

Carbon 78.1 1 per cent. 75-27 per cent. 

Hydrogen 10.96 " 10.80 " 

Oxygen IO -93 " 1 3-85 " 

100.00 per cent. 100.00 per cent. 

Linseed oil is a mixture of linolein, the glyceride of linoleic 
acid, which forms the principal constituent, about eighty per 
cent., olein, palmitin and myristic acids. Nitric acid, of 1.30 
specific gravity, colors linseed oil sulphur yellow, and if the 
acid contains some nitrous acid, yellow-greenish, which, how- 
ever, soon changes to red-brownish. Fuming nitric acid pro- 
duces on the point of contact a red-brown zone, while the acid 
itself is colored green. By shaking the mixture becomes dirty 
cherry-brown, which later on becomes somewhat paler. Sul- 
phuric acid causes first a green color, which, however, soon 
changes to brown. By mixing ten drops of linseed oil with 
three drops sulphuric acid, a red-brown resinous mass is formed. 
A mixture of sulphuric and nitric acids produces, first, a yellow 
color, which changes to gray-green, and, later on, to a dirty 
green-brown. 

Five parts, by weight, of linseed oil, causes the temperature 
to increase from 59 F. to 194 F., a difference of 134 . The 
temperature of linseed oil adulterated with colza oil rises only — 



ENAMELED LEATHER, ETC. 457 

With 5 per cent, of colza oil, to 163.5 F. 



10 " ' 


" 160.0 F. 


15 " 


" 157.0 F. 


20 " " 


" 153-0° F. 


25 " 


" 150.0 F. 


30 " 


" 146.5° F. 



Solution of nitrate of silver causes a somewhat red-brown 
coloring. Zinc chloride produces no effect. Ammonia, potash 
lye and lime water produce yellowish liniments. Caustic alka- 
lies saponify linseed oil very quickly, yielding soaps of little 
solidity. By saponification, linseed oil gives ninety-five per 
cent, of fatty acids and five per cent, of glycerine. The above- 
mentioned formation of a brown resinous mass, by mixing ten 
drops of linseed oil with three drops of sulphuric acid, is very 
characteristic as regards adulterations. In the presence of for- 
eign oils, such as colza, poppy seed, nut, cotton-seed oil, etc., 
the oil does not form a brown, viscous resinous mass. The 
linseed oil alone is changed to a resin, the brown resinous flakes 
floating in the admixed oils. An admixture of fish oils is 
readily recognized by their peculiar odor and taste, or by phos- 
phoric acid, of the consistency of syrup, which colors linseed 
oil yellow-brown, but fish oils red, which is, however, soon 
changed to black-brown. Even Scotch cod-liver oil, which is 
now brought into commerce almost inodorous and of a very 
pale color, shows this change with phosphoric acid. An adul- 
teration with even y^ per cent, of fish oil can also be de- 
tected by the red color produced by sulphuric acid. Concen- 
trated hydrochloric acid added to linseed oil gives a yellow 
mixture. If hemp oil be present, the mixture is yellow-green, 
because hydrochloric acid mixed with hemp oil gives a char- 
acteristic grass-green color. An addition of resin (colophony, 
etc.) is recognized by the white, lumpy precipitate which is 
formed by shaking the linseed oil with spirits of wine, and 
compounding the alcoholic solution with alcoholic solution of 
sugar of lead. 

Linseed oil is extensively used in the manufacture of paints, 
printing ink, varnishes, and in the finishing of enameled and 



458 THE MANUFACTURE OF LEATHER. 

patent leather, leather dressing, etc., and for the preparation 
of water-proof stuffs, floor cloths, elastic rollers, etc. Lin- 
seed oil boiled to the consistency of caoutchouc served form- 
erly for the manufacture of bougies, catheters and elastic 
probes. To prepare such caoutchouc mass, the linseed oil is 
brought to a very thick consistency by boiling for at least 
twenty-four hours, and is then boiled a few hours longer with 
diluted nitric acid. The mass is plastic, and becomes hard on 
contact with the air. By dipping in hot water it regains its 
softness, and on cooling solidifies again to a caoutchouc-like 
mass. 

Linseed oil is sold under four different forms, viz. : raw, re- 
fined, boiled and artists' oil. Of these, by far the most im- 
portant, commercially speaking, is the boiled. The selection 
of the oil to be boiled is a matter of the utmost consequence 
to the oil boiler and varnish maker, since the beauty and dura- 
bility of the paints mixed with it depend largely upon its qual- 
ity. If the seed be not fully ripe the oil expressed abounds in 
mucilage, water and pulpy matter, while more or less acid is 
also present. If, on the other hand, the seed be full grown and 
ripe, the oil is limpid, pale colored and of a highly refractory 
power. To summarize the chemical changes induced in lin- 
seed oil by exposure to the air, it may be said that the oil 
dries, or, in other words, that it passes, by mere absorption of 
oxygen from the atmosphere, from a fluid to a solid state. 
From this known property was derived the theory that it was 
necessary to heat with certain metallic acids from which the 
oils might derive oxygen previous to its exposure to the air, 
thus shortening the time subsequently needed for complete ab- 
sorption. Various oxides were made use of for this purpose ; 
plumbic oxide (litharge), red lead and anhydrous binoxide of 
manganese. More recently the last two named oxides have 
been employed conjointly, and to these agents have been 
added lead oxide or plumbic acetate, zinc sulphate, etc. The 
occasional addition of umber serves only to deepen the color 
of the oil. 



ENAMELED LEATHER, ETC. 459 

The reasons for boiling linseed oil are principally two : First, 
that drying may be facilitated when the oil is spread upon thin 
surfaces, either alone or mixed with paints. The second, that 
it may serve as a vehicle for the mechanical suspension of the 
finely divided particles constituting a paint, thus enabling them 
to adhere to the surface on which they are spread. 

It must not run into drops, nor must it leave the coloring 
matter behind ; the color must be carried by it, evenly diffused 
over the whole surface over which the paint is laid. The object 
to be obtained is to secure a coating impervious alike to liquids 
and gases. It may sometimes happen that even when the 
process of boiling has been performed properly, and with the 
utmost care, the result may prove unsatisfactory to the con- 
sumer. This may somtimes be traced to circumstances entirely 
independent of the process of manufacture. The quality of the 
seed, green or ripe, new or old, the climate, and the soil in 
which the seed was grown — all of these exert a marked in- 
fluence upon the product. The different varieties of seed call 
for separate and distinctive treatment. All oil boilers should 
test the drying qualities of each batch of oil. 

One tried and approved test is to dip into the oil, when cool, 
a piece of well-sized paper, which is afterwards hung up to dry. 
Thoroughly well boiled oil will produce a crystalline surface 
over nearly the entire portion of the sheet dipped in the oil. If 
the boiling has been imperfect, the upper portion of the paper's 
surface will simply be greasy, and only the lower portion will 
show the varnished coating. When the touch of a finger to the 
submerged portion of the paper shows no grease adhering to it, 
the boiling may be said to be complete. Reference has already 
been made to the use of heat for the purpose of driving off the 
mucilage from the seed, The philosophy of the process con- 
sists in the throwing off of the water (probably held by the 
mucilage) a yellow froth mounting to the surface of the grad- 
ually heating oil. The continued application of the heat 
evolves numerous gases. Before the attainment of the result 
hoped for from the heat, however, a temperature of between 



460 THE MANUFACTURE OF LEATHER. 

6oo° and 700 F. has been obtained. When the partially de- 
structive distillation has effected the desired change in the oil, 
the liquid assumes a deep, permanent (sometimes reddish) 
brown. 

In the opinion of some manufacturers, the depth of this 
brown is the best test by which to gauge the thoroughness of 
the boiling. The old-fashioned way of fire heating has been to 
a very considerable extent abandoned, steam being* employed 
as a substitute. 



CHAPTER XXX. 

HORSE LEATHER. 

THE manufacture of horse hides for footwear originated in 
Denmark, and from there it followed the coast of the Iberian 
peninsula, and was largely developed in Hamburg. There it 
took root immediately and was developed gradually to the 
highest degree of perfection. 

From Hamburg the art spread to Austria, Poland, the 
Russo-German provinces and Scandinavia, which have each 
manufactured some very handsome horse leather footwear. 

England and France are also manufacturing this leather to 
some extent; but in the United States there is but little done 
in this line of manufacture. At the Philadelphia Exhibition in 
1876 all other kinds of leather produced in this country were 
exhibited, horse leather being the only exception. 

The proper method of liming and working out these hides in 
the beam-house is the foundation for a good finished product. 
The tanning of horse hides is not generally understood in this 
country, simply because the work in the beam-house is not 
properly comprehended. It is conceded by all that in the 
vicinity of Hamburg and Bremen and in Holstein, the tanners are 
experts in turning out horse butts. These are limed differ- 
ently from any other raw material. The hides are soaked 
three or four days, according to the time of year. They are 
fleshed the second day in soak. After that, put them in a very 
foul lime. If it is not foul enough to suit, add hen manure to the 
lime, so that the hides will be very slippery on the flesh side. 
This makes them very flacculent, so a deep impression can be 
made with the finger. As soon as the hairs are loose, put the 
hides in a strong lime made with fresh water; for every 15 

(461) 



462 THE MANUFACTURE OF LEATHER. 

butts three gallons of unslaked lime. After slaking, the lime 
is allowed to cool off thoroughly. The hides are then 
handled immediately, and for three days twice a day. This 
strong lime swells them up greatly, thereby loosening the 
so-called " Spiegel." The unhairing is next done, and the 
flesh shaved off the butts thoroughly. They are then bated in 
hen manure. They are required to be so slippery on the 
grain side that it would be difficult to hold them, and the dirt 
is thoroughly worked out of them. Stamping in warm water 
is the next process. The butts are put in fresh water over 
night and in a very light oak liquor. 

The usual time which the sides remain in the handling 
liquors is six or seven days, and they are then laid away twice 
in ground bark, both lay-aways extending through about 
seven weeks. 

Upon being removed from the second lay-away the sides 
are hung on poles and exposed to the open air to harden, and 
are then dampened and split, but the operation of splitting 
horse hides by machinery is much more difficult than that for 
other species of hides, and requires considerable experience. 

In Hamburg, Germany, where a large quantity of horse 
leather is manufactured, the splitting machine is not employed, 
the custom being to soak, unhair and flesh the hides, and then 
to cut the butt at once by taking off a few thicknesses with the 
fleshing knife. 

The sides split by the splitting machine are next flattened 
by having their shanks and bellies leveled off with a currier's 
knife. 

From this point the process of tanning and currying horse 
leather is the same as has been described for the side of upper 
leather. 

Horse leather is also finished in imitation of kangaroo and 
other grains. 

Cordovan. — Horse hides for shoe purposes usually have the 
butt or shell cut out in the tanyard ; they come into the cur- 
rier's hands with the hind shank left on. The first process is 



HORSE LEATHER. 463 

to soak them down, after which the mane is cut out, the shanks 
removed and the hides split down the back. They are then 
slicked. We find the best way is to slick them well on the flesh 
side ; it extends the hide more, and less weight is taken off. 
Generally they are shaved over when they are in sides ; the 
bellies are then cut off, so that the only beam work required is 
to level the thick parts for cordovan. With regard to the 
soaking, we find that sumac liquor is preferable to water; it im- 
proves them, and does not wash out the tan. After shaving, 
the hide should be scoured on both flesh and grain side, taking 
care not to "fur" or break the grain. There is generally a 
great deal of " bloom " or dirt, gathered from the tan, that 
must be carefully cleaned from the grain. By doing this, the 
grain becomes open and the leather softer, allowing it to absorb 
as much as possible of the sumac liquor, commonly called 
" compo " in the trade. After scouring they are placed in the 
" compo " and well handled once or twice a day. Every time 
they are handled they should be laid up for an hour or two 
before being again placed in the " compo." If they are well 
tanned, two or three days is quite sufficient for them to lie in it. 
The liquor should be warmed every day. When finally taken 
out of the liquor they are slicked out, either on the flesh or grain 
side; the flesh is better, as it leaves the "compo" in the grain. 
After hanging in shed, in order to stiffen a little, they are taken 
down and set on the grain side, which should be well oiled and 
as much dubbin put on the flesh side as the substance and 
quality of the leather will carry. 

They are then re-hung in the shed until quite dry. They 
should lie a few days in the grease before blacking (called in 
the trade seasoning). The blacking should be done on the 
grain side, and if the grain is in any way damaged they should 
be first buffed with a turned slicker or knife. When the black 
has well gone into the grain, bottom size and hang them up to 
harden. Then dubbin them again and lay them by for a day or 
two, taking care that they do not get dry. Afterward set them 
off" on the flesh and on the grain with a dull slicker, and hang 



464 THE MANUFACTURE OF LEATHER. 

them in a good warm stove to dry off. The flesh side is then 
cleaned, the grain is slicked with a dull slicker and some dub- 
bin rubbed in. After laying by for a few days the grease is 
slicked off, the finishing size put on, and the cordovan is ready 
for sale. With regard to the "compoing" where a drum is not 
used, the best way is to put it in large tubs or vats and well 
handle the hides. 

One of the most notable and distinguished achievements in 
the production of chrome leather, which deserves to be chron- 
icled, is in the making of a wax finish on chrome-tanned horse 
hide butts (cordovan) and on calf skins. This has been 
accomplished by Hahn & Stumpf, of Harrison, N. J., who use 
the Dennis one bath system of chrome tanning. The firm also 
make a chrome tanned horse hide front, with a kangaroo finish, 
which is certain to find favor with shoe manufacturers. The 
chrome tanned and wax finished cordovan goloshes and calf- 
skins are, however, a distinct and important advance in the art 
of leather making, and young Henry Stumpf is deserving of 
much credit for his ingenuity in accomplishing this result. 
The writer has seen this leather, and is well convinced that it is 
superior to the old style of bark tanned wax leather. Messrs. 
Hahn & Stumpf will undoubtedly secure a large and increasing 
trade among shoe manufacturers with their new line of chrome 
tanned leather. 

Many horse hides are bought and sold in Hamburg, Ger- 
many, where dealers say that if Americans made a more thor- 
ough selection there would be a great increase in their pur- 
chases of horse hides. Mule and horse hides should be sepa- 
rated. Mules are unknown in Germany. Horse hides should 
be classified into primes, seconds and thirds, and into sizes. 

Horse Hides for Enamel. — These are generally split down 
the back, the shank removed and dressed in sides. They are 
shaved very level, scoured on flesh and grain, put into some 
good sumac and well handled for a day, then taken out and 
slightly slicked off on the flesh. Some linseed oil is then put 
on them and they are put in the shed, hanging them as wide 



HORSE LEATHER. 465 

apart as they possibly can be to get stiffened. When fit to take 
down set them well on the flesh and the grain, and roll them 
with a straight or cross-grained roller ; hang them in the shed 
to dry; when dry take them down, stone well on the flesh, 
whiten them over the beam or with a turned slicker, then 
bruise on the flesh and slightly run the grain up. They are 
then ready to be enameled. 

Horse Hides for Plain Enamel. — Are dressed in the same 
manner as grain enamel, with the exception that they are buffed 
all over on the grain, and are generally shaved much thinner 
than the grain ; they also are not rolled or printed ; when dry 
they should be whitened. After being well stoned on the 
buffed side, as well as bruised on the flesh, they are ready to be 
enameled. 

Horse Hides for Memel. — Some are dressed in sides, others 
without the bellies on, and the butt pieces cut off and dressed 
for cordovan, but the bellies and shanks are sometimes put on 
for memel. They are shaved, scoured and " compoed," slicked 
out of compo on the flesh, then hung up in the shed to samm 
or stiffen. When sufficiently stiff, they are set and printed on 
the grain, then stuffed on the flesh and hung up to dry. When 
dry, they are seasoned and bottom sized and a little oil put on 
the grain. When a little stiffened, they should be grained up 
so as to make the print of the .roller show up well. Then put 
them in the hot room or shed to get thoroughly dry. The flesh 
must then be cleansed. Raise the grain again, oil them off and 
they are fit for sale, to be cut up for shoes or any other purpose. 
30 



CHAPTER XXXI. 

ALLIGATOR LEATHER. 

A FASHIONABLE material for small valises, satchels, porte- 
monnaies, cigar cases, etc., is the skin of the alligator, and in 
addition to uses enumerated it has also been employed for 
uppers of men's and women's shoes. 

In all the Gulf States, from Florida to Texas, these saurians 
are hunted to supply the demand. 

Alligator leather has been in vogue for a long time, but dur- 
ing the past fifteen years the slaughter of the alligator has been 
prosecuted with great activity. 

R. W. Smiley and B. M. Gopelrivitch, special agents of the 
Census Bureau, completed a tour of the bayou district of 
Louisiana, having traveled over 1,000 miles through the net- 
work of bayous, lakes and bays. Among the subjects investi- 
gated by them was that of alligator hunting, formerly an indus- 
try of no little importance in Louisiana, giving employment to 
several hundred men and furnishing a large amount of leather 
quite popular in the manufacture of shoes, trunks, bags, etc. 
This industry, which reached its height about ten years ago, is 
reported to be nearly dead, confined to a very few bayous and 
lakes, the saurian population of the state having been destroyed 
by the hunters. 

The alligators now killed are much smaller than formerly. 
There are stories of saurians of the past forty feet in length, 
but they are probably apocryphal, and from twelve to sixteen 
feet will represent the largest of late years. They have now 
dwindled down to barely half this size, and are so scarce that 
one can travel an entire day through the swamps without see- 
ing one, and a great majority of the people in Southern Louis- 

(466) 



ALLIGATOR LEATHER. 467 

iana have never encountered a wild one. There are very few 
breeding alligators left, and the saurian will probably be extinct 
in the State in the next ten years, except a few tame ones kept 
in the parks. 

Notwithstanding the reports to the contrary, the alligators 
were rather innocent animals. Occasionally they stole young 
pigs, and there is a tradition that they had a weakness for pick- 
aninnies, but there are not over half a dozen cases recorded of 
people being hurt by them, and they seemed thoroughly indis- 
posed to attack man. They succeeded, however, in keeping 
the streams of the State nearly destitute of fish, and the fishing 
will probably improve with their destruction, now so imminent. 

Brazil is now our chief source of supply for alligator skins, 
which are only of fair quality. 

These skins are usually packed for shipment in barrels and 
are green salted. The salting is often poorly done, and if the 
skins are allowed to remain too long in the barrels they become 
heated and the grain sides thereby so injured that they have to 
be finished into second-class leather. 

Only the skin from the belly and sides is used ; the back 
with its heavy coat of scales is cut out and thrown away as 
worthless. 

All the skins show great uniformity, being of a bluish black 
hue on the sides and a peculiar bluish white under the belly, 
and each skin is curiously checkered in oblong divisions, which 
being separated by intersecting grooves, and wrinkled, give the 
peculiar appearance seen in all alligator leather. 

The trade in these skins receives them of all sizes from three 
feet up, the average prices paid at New Orleans, La., ranging 
from fifteen cents each for the smallest to about one dollar for 
the largest. The skins most in demand are about seven feet 
long. Those of the monster alligators ranging from ten to 
fifteen feet long are not much desired. Under the continual 
destruction of alligators the supply is rapidly diminishing, and 
it is now but a question of a few years when it will be impos- 
sible to obtain these skins at a price that will justify their gen- 
eral employment. 



468 THE MANUFACTURE OF LEATHER. 

To supply the demand for cheap articles, imitation alligator 
leather is now being largely produced. 

The alligator leather of this country and the kangaroo leather 
of Australia are similar in the respects that they both depend 
upon wild animals to supply the material for their manufacture, 
and the business is therefore to some extent precarious. 

At the place of shipment, the skins from young, middle- 
aged, and old alligators are thrown promiscuously into barrels, 
and the first step when they arrive at the tannery is to assort 
the small and medium-sized from the larger ones, which are 
kept separate. 

The skins are then thrown into vats containing clear, cold 
water, and in these soaks the smaller ones remain about two 
days and the large ones four days. 

They next go into vats of lime, which should not be so strong 
as for depilating, and remain from eight to fourteen days, ac- 
cording to size. 

Each day the skins are reeled into stronger lime, great care 
being observed not to rot the tender portion during this swell- 
ing. 

The bate of hen manure, into which they next pass, is made 
quite weak, and in this bate the skins are gently agitated by 
means of the usual England wheel, the period for which they 
remain being from ten to fifteen hours, according to size. 

They are next cleansed in a wash wheel and then thrown 
into a vat containing hemlock liquor of about 4 strength, and 
every other day are shifted into stronger liquor, until at the 
end of about twenty days it has been increased to about 20 
strength. 

A gentle agitation of the tanning liquor during the last twelve 
days is very beneficial, as it aids in the more thorough tanning 
of the skins, and prevents the settlement of the sediment of the 
liquor into the creases, which is liable to rot the tender portions, 
especially those of young alligators. 

After being subjected to the tanning process just described, 
the skins are hung in the open air to harden. They are then 



ALLIGATOR LEATHER. 469 

carried into the finishing room, and eight or ten skins are piled 
one upon the top of another and placed in a clamp, the flesh 
side being uppermost. The flesh sides are then softened by 
the operator with a tool, the object being to throw up the 
rougher portions, which are then lightly cut off with a currier's 
knife. 

If the skins are intended to be manufactured into upper 
leather they are again placed in the tanning liquor of 8° or io° 
strength, and in this they remain for six or eight days, during 
which period they are gently agitated. 

After being removed from the final tanning liquor the skins 
are scoured by hand on a slate table, first on the flesh and next 
on the grain side, the tools used being the scouring brush, stone 
and slicker. 

After being scoured they are placed in the air to harden, and 
when not quite dry they are carried into the shop and stuffed 
by hand, tallow, fish oil and a small quantity of rosin being used. 

They are next "set out" and are then carried to the finishing 
room and blackened on the grain side with a preparation of 
logwood and copperas. 

They are next glassed by hand, and if a gloss is desired they 
are "pasted over the black" and hung up in the finishing room 
to dry over night. 

In the morning the skins are re-glassed and immediately fin- 
ished by gumming them over on the grain side with a prepa- 
ration of gum tragacanth, and are then measured and ready for 
market. 

The skins not intended for the manufacture of upper leather 
are not blacked, but are finished in their natural color, which 
is a yellowish-brown, and are used for satchels, pocketbooks, etc. 



CHAPTER XXXII. 

RUSSIA CALF. 

To make colored or Russia calf, get as good a selection of 
green skins as possible, and free from salt rust. Soak in packs 
of convenient size, and so that the skins in each pack are not 
too widely different in weight. The number of skins in a pack 
should be controlled by the size of the soaks, limes, and tan 
vats. The following quantities of green skins will make con- 
venient soaks in paddle vats of 700 gallons, with good inflow 
of water, during time of soaking. We would say 400 five-pound 
skins, 300 six-pounds, 250 eight-pounds, 200 ten-pounds, and 
150 twelve to fifteen pounds. 

Trim and soak ten to sixteen hours, according to season of 
year and necessity of hurry. About ten hours' soaking in the 
summer is usually sufficient for ordinary stock. Dry skins 
should be milled five hours or more after soaking so as to 
soften properly and be in good condition for the limes. It is 
very important that skins be fairly well broken in the hide mill, 
or they will cause trouble. Make up limes 60 parts of lime 
and 35 parts of sulphide of sodium. Both materials to be dis- 
solved in a barrel of warm water before putting in the vat. 
Swab each skin before putting in the vat, by dipping flesh in a 
box of large size containing solution of sulphide and lime in 
same proportion as in vat. As each skin is transferred from 
swabbing box to vat they should be immersed by being shoved 
down with a pole. Haul on the following day and strengthen 
with same proportion of sulphide of lime. Put back and haul 
again on the fifth day, and strengthen, and the skins will be 
ready for unhairing on the eighth or tenth day. 

From the limes or beam house the skins should go into a 

(470) 



RUSSIA CALF. 47 I 

rapidly revolving wheel pit, with constant inflow of water. 
Wash thoroughly three or four hours until water is clear and 
the skins free of lime. Then flesh on the machine and fine- 
hair the grain if possible. Leave in clear cold water over night 
or at least for five hours before bating. The lime and sulphide 
dissolve the hair completely and give a soft skin. The new 
bate can be made by using three bushels of hen-manure, or 
two bushels for renewing the old bate or pure. The liquors 
should be 90 F. Before putting back into bate, use wheel 
pit for this work and keep stock constantly in motion during 
this operation. After puring, rinse well and work on flesh side, 
then put skins into luke-warm water in tub before working 
well on grain. Then wash thoroughly in cold water and let the 
skins drain before putting them in tan vat. By this method 
of depleting, packs can be thoroughly reduced in three hours 
and then worked so that they can be put in tan the same day. 

In tanning use wheel pits of convenient and uniform size, 
each containing about 700 gallons of liquor. Divide tan-room 
into three divisions. First — Sufficient vats for handling and 
coloring. Second — Vats for continuing tanning from the strik- 
ing liquors to the time of skiving. Third — Vats for tanning 
out stock after skiving. 

Liquors should be four to five degrees barkometer. Into the 
water pits should be put six or seven pails of gambier liquor 
standing 75 degrees in the pails ; also four or five pails of sedi- 
ment gambier after the boiling. When the liquor is ready, im- 
merse the stock and run the paddle wheel 30 to 40 minutes to 
assure a good, uniform color on grain. Strengthen twice daily 
with two or three pails gambier and sediment, morning and 
evening, and run wheel three times daily, ten to fifteen minutes 
each time. Continue in this manner four or five days. Then 
haul packs and strike out flesh on machine. Now transfer to the 
second and stronger liquors of eight or ten degrees. Hold packs 
in this'liquor for 14 days, moving them around in the vats by run- 
ning the wheel three times daily from eight to ten minutes each 
time, and strengthen with two or three pails of gambier, meas- 



472 THE MANUFACTURE OF LEATHER. 

uring 75 degrees, in the pails. This should be done once daily 
for 14 days, when stock will be about struck through. With- 
draw and set out on flesh by machine. Then skive and put 
back in third section of finishing liquors of 12 to 15 degrees for 
seven days. Strengthen each day with two pails of gambier> 
and run wheel each time 10 to 15 minutes. This wheeling or 
turning over of the packs hastens the tanning and changes the 
position of each skin in the vat, thus assuring a uniform color 
on grain. By using one pail of salt per vat each week the 
liquor will be kept sweet and the tanning done more rapidly- 
Striking or coloring liquors should be run down the sewer after 
each pack is removed, as such liquor is dirty and worthless 
after a week's use. 

After the stock is tanned out, it may be strengthened and 
cleared by running in drum with seven pounds alum and five 
pounds salt to every 125 skins. Use seven pails of water for 
dissolving this material. After running for thirty minutes» 
horse the leather for five hours, so as to drain well. Then oil 
in drum, using five quarts neatsfoot oil to every 125 skins. 
Keep drum turning thirty minutes in oil. Then stop, withdraw 
the pack and use machine for setting out flesh. Then hang in 
loft to dry. 

As the majority of Russia tanned skins need cleansing be- 
fore shaving to the desired substance required by the tanner, it 
is necessary to remove the excess of tan or other surplus matter 
by washing in a mill, using twenty pails of water to each 125 
skins. The water should be 70 F., and the stock run in it 15 
or 20 minutes — no longer. From the drum, set out on flesh 
side on machine. Then oil on grain by hand with neatsfoot 
oil, and dry out in moderately warm room. 

After the stock is dried, wet down and horse up ; drain five 
hours before shaving. After shaving, fat-liquor as follows : To 
each 60 skins use two gallons of fat liquor and one pint of birch 
oil well beaten into the fat liquor. Run the stock 30 minutes, 
and then set out on flesh by machine and grain by hand. Use 
glass on grain ; then put on hooks to dry slowly. When dry 



RUSSIA CALF. 473 

take down to color, using 100 pounds of dry leather to each 
batch colored. Give each of the 100-pound batches seven pails 
water, 90 F., in drum to wet up stock before coloring. Run 
stock 25 minutes. Drain off any excess of water not taken up 
by the leather. Throw stock well up on each side of the door 
of drum, so that no skin will lie in dye before starting the drum 
in coloring. Boil up dyes with one pail water, and add six 
pails water of 8o° F. to stock in mill ; then add dyes and start 
mill immediately. Run stock twenty minutes in dyes and to 
each change of dyes. 

After coloring and before removing from mill, drain off any 
excess of dye and apply egg, using one pint of egg-yolk to 
each dozen skins. Run stock in egg for fifteen minutes ; then 
horse up from mill and put on hooks to dry. When dry, lay 
in sawdust to dampen for staking. Stake well on machine ; 
then trim, and, if stock requires it, use three gallons of fat 
liquor in six pails of warm water. In wetting down stock to set 
out, the latter should be done carefully on flesh and grain. 
Then dry out and brush on grain with powder brushes. Season 
and pack down four or five hours before rolling. Roll hard 
and air off in warm room. Stake light on grain and roll light. 
Then measure the stock, which will then be ready for shipping 
away. 

ANOTHER PROCESS FOR COLORING. 

After shaving skins to uniform substance for the work in 
hand, fat-liquor and set out on flesh by machine, and grain by 
hand. Dry cut; then take 100 pounds dry leather in one 
batch for coloring. Put stock in drum with twenty-five gallons 
water of 90 F. Run stock fifteen minutes in water, then 
drain off any excess of water not taken up by stock in drum. 
Bail up dyes in one pail water. Give stock in drum six pails 
water of 8o° F., and add dyes. Use the same amount of 
water to each change of dyes and run stock twenty minutes in 
each change of dyes. 

After coloring, rinse in clear water and egg, giving a propor- 
tion of two egg yolks to each skin colored. 



474 THE MANUFACTURE OF LEATHER. 

Color No. 2 is composed of the following dyes 



ist Dye. 
8 ozs. Acid Brown N. 
4 ozs. Orange D. 



2d Dye. 
86 ozs. Nankin. 
% oz. Methyline O. 
6% ozs. Bismarck Brown R. 



Color No. 3: ist dye — 15 ozs. acid yellow, F. ; 2d dye- 
1 y^ ozs. Bismarck Brown R : 15 ozs. aniline yellow. 



Color No. 4 is made up as follows 



ist Dye. 
40 ozs. Bronze No. 2. 
1 3 ozs. Acid Brown N. 
1 8 ozs. Orange D. 



2d Dye. 
84 ozs. Nankin. 
32 ozs. Bismarck Brown R. 
22 ozs. Leather Brown No. 2. 



After coloring, dry out in room of 8o° to 90 F. When 
dry put in sawdust and dampen to stake. Stake well, then wet 
down to set out. Set flesh on machine and grain by hand. 
Dry out in moderately warm room. When dry, brush with 
power brush on grain, then season, using seven quarts vinette 
and whites of two eggs in two and one-half gallons water. Use 
flannel pad to apply seasoning. After seasoning, pack down 
grain to grain. Let lie four hours. Then roll hard, air off in 
warm room. Stake lightly on grain. Roll lightly and stock 
is ready for shipping room. For the above description we are 
indebted to Hide & Leather, of Chicago. 



CHAPTER XXXIII. 

THE MANUFACTURE OF RUSSIA LEATHER — RUSSIAN METHOD 

OF PREPARING AND APPLYING THE MORDANT AND 

DYE — MANUFACTURE OF BIRCH OIL. 

THE MANUFACTURE OF RUSSIA LEATHER. 

In Russia a variety of leather is made called Juften, or in- 
correctly Juchten (Russia leather). It is a well- tanned leather 
of unusual strength, great flexibility and almost impervious to 
water. Moreover, it is not attacked by insects, because it pos- 
sesses a penetrating odor very disagreeable to them, but so 
acceptable to many men that they perfume their linen with 
pieces of the leather, or carry pocket books, cigar cases, or the 
like, made from it. 

Russia leather attracts a great deal of attention on account 
of its peculiar odor, and in other countries frequent attempts 
have been made to impart a similar odor to other kinds of 
leather. 

Russia leather is employed more for articles of luxury than 
of utility, and does not moulder under the influence of damp- 
ness. 

But its use for book-binding in the numerous public libraries 
of this country is being rapidly superseded by red-colored 
Morocco leather, which is attractive, more durable, and less 
costly. 

Russia leather is also much used in the manufacture of 
jewelry cases, handkerchief cases, and other toilet articles, also 
for albums, traveling bags, etc. 

It derives its name from the country whence it originated, 
and where it is more especially manufactured. 

It is a fact now established that tanners of other countries 

( 475 ) 



476 THE MANUFACTURE OF LEATHER. 

are well able to produce an article very similar and very much 
cheaper than real Russia leather, but, however, minus its fine 
odor. In a paper published on the manufacture of leather in 
Russia, written by two officials in the Russian War Office, the 
peculiar odor imparted to the leather was attributed to the tar 
extracted from the birch tree. After the Exhibition at Phila- 
delphia, a company of American leather manufacturers purchased 
200,000 puds of the oil (1 pud = 36 pounds), but the results 
obtained with it were anything but satisfactory. The price of 
this birch-tar oil varies from 3 to 4 roubles per pud ; the oil, 
however, is so much adulterated that Russian leather manu- 
facturers, as a rule, are provided with means of their own for 
its preparation, and in Germany an essence is made by Dr. C. 
Heintzel, of Luneburg, which gives to leather an odor very 
nearly approaching to that of Russia leather. 

The Russia leather manufactories are situated mostly in the 
districts of Viatka, Orel, Iver, and Kasan, where are numerous 
birch forests. Here the hides of young cows are especially 
used for the manufacture of Russia leather — white, red, and 
black. The raw or wet hides, in order to deprive them of hair 
and flesh, are laid in lime or ashes mixed with lime, and they 
are kept there until the hair begins to loosen. After the un- 
hairing, the hides are placed in the vats for swelling, then 
washed in running water, cut, salted, placed in a receptacle 
containing a mixture of flour and warm water and shaken and 
turned about vigorously. By this means a fermentation is set 
up, and the acid thereby produced takes away the last remains 
of the lime. This is the oldest mode of operation and the one 
most in vogue, but in some tanneries the process varies. 

The tanning should begin with the placing of the hides in 
the pits, and with their treatment in weak liquor, and there are 
four shifts which last over 20 or 25 days. About 46 pounds of 
bark are used on an average for each hide. After being rinsed 
and sorted, the hides, being still damp, though not wet, are 
spread, grain-side downwards, upon a table, and smeared with 
a mixture of birch-tar and melted fat. Every hide intended 



RUSSIA LEATHER. 477 

for white or red leather receives in this way one-half pound 
of tar and one pound of fat. The mixture is put on carefully 
with the hand so as to be perfectly smooth and equal. When 
this is done the hides are hung out in an open shed to dry. 
Those intended for red leather are smeared in drying with a 
solution of alum, and the grain side of each hide treated with 
sandalwood dye put on cold. Those intended for black leather 
are rubbed on the grain side first with a solution of alum, and 
next with a solution of logwood put on almost boiling hot, and 
then, to set the color, brushed over with a solution of green 
vitriol (sulphate of iron). In some cases, instead of the vitriol 
a liquor is used which is obtained by p^Lting old rusty iron 
into an acid decoction gone into a fermentation and called by 
the workmen " quass." The hides are then once more rubbed 
over on the flesh side with birch-tar and melted fat in the 
proportion of one-half pound to each hide. If, however, the 
production of the so-called birch-tar leather is aimed at, one 
and a half pounds of each substance is taken. 

As a final preparation the leather is softened in water and 
thoroughly worked upon the tree, smoothed and kneaded, and 
afterwards rubbed briskly with the graining tool, and lastly with 
a tool of glass, stone, or steel on the grain side, alternately 
rolled, and greased a little on the grain side. The black leather 
is also smeared on the grain side with a mixture of birch-tar 
and fat. 

In other processes of tanning, the hides after being unhaired 
and fleshed are piled up with alternate layers of ground willow 
bark in great vats, and then covered with a solution of willow 
bark. They are moved from ten to six times in the tan pit, and 
the spent bark is each time replaced with fresh, until the tan- 
ning is completed. In Russia the hides of cows or young 
bullocks are employed by preference, and horse hides are also 
used, especially in the interior of Russia. In France, however, 
these hides are hardly employed at all, but only the skins of 
rams, goats and calves. This is done because the French 
Russia leather is principally used in book-binding or for cover- 



478 THE MANUFACTURE OF LEATHER. 

ing cases and similar work, for which that made in Russia is 
entirely unsuitable, in the first place because it is much too 
coarse, secondly, because it is so permeated with fat as to 
render it undesirable for the purposes mentioned. 

In the preliminary preparation for tanning, it is essential that 
the hides be entirely freed from lime. The Russians employ a 
peculiar process for this purpose, which is, however, as the re- 
sult shows, very effective. They swell the hides for several 
days in an acid bath composed of rye and oatmeal and water, 
to which a sufficient quantity of leaven is added to set up fer- 
mentation in the whole mass. 

After this operation has been completed, the hides are tanned 
first in oak tan, then in willow, and finally to remove their stiff- 
ness are softened in a flour pap. This is composed of about a 
pound of rye flour for each hide, and ten pounds of salt to 
each four hundred hides. After they have laid in this mixture 
several days, they are washed off, dried lightly, and then 
greased with a mixture of two parts of train oil and one of birch 
oil. Of this mixture about half a pound is used for each cow 
or horse hide. It is well rubbed in upon the flesh side with 
the flat hand, and left for some days to take full effect, which is 
generally secured by hanging the hides under an airy shed. 
This completes the process as it is generally carried on with 
them. 

Russia leather is also manufactured in Austria, where it is 
tanned with tan-bark. Austrian tanners do not understand the 
art of bringing out the natural grain, so they give their Russia 
leather an artificial grain, produced by lines which intersect 
each other at acute angles, thus forming rhomboidal lozenges. 
The false Russia leather may be at once recognized by this 
regular artificial grain, which the Russians never produce. 

In order to obtain the birch oil the Russians proceed just as 
the Polish peasants do in the preparation of their pine-tar. If 
they are especially careful, they do not dig a pit in the ground, 
in which to place the wood to be distilled, but employ two 
large pots. The two pots are filled with the cork-bark of the 



RUSSIA LEATHER. 479 

birch, each one having a little opening in the bottom, by which 
ventilation is possible. The sides of the pots, which are placed 
one above the other, are smeared with clay. The bark in the 
under pot is ignited through the opening, this is placed upon 
another empty pot, and the whole is left to itself. In the bot- 
tom pot there collects considerable tar, quite a quantity of im- 
pure wood-acid (pyroligneous acid), and upon this floats the 
clear birch oil. This process may be called the rational one, 
but the customary way is to dig a pit in the ground, cover the 
sides with clay, and dig a ditch at the bottom of the pit, in 
which is placed a cask or barrel to receive the tar and other 
products of distillation. The pit is then filled with birch bark, 
which is piled up in the shape of a mound. This is covered 
with sod, in which at various places air holes are made, to 
permit the exit of the smoke and the entrance of air. Al- 
though both processes are very crude and yield only poor re- 
sults, they suffice for the needs of the uncleared Russian forests, 
where raw material costs nothing. In America, if birch tar or 
oil is desired, it is secured by dry distillation, by heat applied 
from the outside, whereby everything that is in the wood is 
saved, and all that is left in the vessel in which the distilling 
is done is good charcoal. 

The birch oil, which is lighter than water, transparent and 
moderately volatile, is mixed with train oil in varying pro- 
portions, from one part train to two of birch oil or the exact 
reverse. This latter oil is called in Russian daggeat. If the 
green buds and young twigs of the birch be distilled by them- 
selves, they give an agreeable oil smelling something like rose 
oil. This the French claim to use for the preparation of the 
finer sorts of Russia leather. Since, however, these do not 
smell in the least like rose oil, either the claim concerning the 
oil, or the statement that it is used in their preparation, or both, 
are untrue. In fact, there are many different claims made con- 
cerning the manufacture of Russia leather; this is partly due 
to the actual employment of varying processes, partly to the 
fact that the travelers from whom the information comes, not 



480 THE MANUFACTURE OF LEATHER. 

being skilled in the craft, either understand what is told them 
incorrectly, or actually receive false information. This last 
happens especially with uncultivated people, who having only a 
meagre industry, are especially jealous of it, and do not will- 
ingly give information concerning it to strangers. 

The red color of Russia leather is caused by a surface dye- 
ing with sandal-wood or Guinea red-wood or Sanders wood. 
After the hides are tanned they are soaked in alum water, 
placed together two by two in a sack, and covered with the 
dyeing liquid. If the leather is desired to become black, 
sulphate of iron is added to the wood decoction. The greasing 
is always the conclusion of the process, and after the hides are 
placed on poles, about which they are wound many times, and 
stretched and pulled to give them the necessary flexibility. 

The method of manufacturing this leather we shall now de- 
scribe as it is conducted in the United States, for the reason 
that the machines here employed are so much superior to those 
used in Russia that an article almost equal to the native Russia 
leather is produced, and in a much shorter time. 

The hides used in the production of this leather are generally 
cow or steer hides and large calf-skins, seldom goat or sheep- 
skins. 

In tanning, the first operations, such as soaking, unhairing, 
fleshing, etc., are conducted in the same manner as for other 
kinds of leather. 

The swelling of the hide is one of the essential points for its 
successful manufacture, and is proceeded with in the following 
manner : For one hundred cow or steer hides take twenty-two 
pounds of rye flour and ten pounds of oat flour, and knead with 
yeast and a little salt. 

Allow this dough to ferment, and then thin with sufficient 
water to immerse the one hundred hides, which are left in this 
preparation for forty-eight hours, and when they are sufficiently 
swollen, the hides are placed in a tepid solution of willow and 
poplar barks. The hides are handled in this solution, twice a 
day, for at least eight days. They are next immersed in a 



RUSSIA LEATHER. 48 1 

liquor, the tanning ingredients of which are composed equally 
of oak, pine, and willow barks, and in this liquor they must also 
be handled at least twice a day. After eight days the last- 
named liquor is renewed and the hides are hardened and split, 
and then again placed in the liquor for another eight days, care 
being observed to handle as before. After this time the hides 
are sufficiently tanned. 

The period of tanning can be considerably shortened by- 
using a revolving-wheel, placed over the tan-vat to gently agi- 
tate the liquor, such as the England wheel. 

After being tanned the hides are cut into sides, and scoured 
and then rinsed in clear water and allowed to drip and dry. 
The sides are then slightly dampened and allowed to temper 
for two days and then greased with a mixture of birch oil and 
seal oil, two-thirds of the first and one-third of the second, ac- 
cording to the thickness of the leather. 

For heavy leather a coat of this grease is applied to the grain 
side. The leather is then thoroughly greased on the flesh side, 
and afterwards fulled. The leather is next set out, then 
whitened, and finally boarded, and when well dried it is pre- 
pared for dyeing. 

Before dyeing, the sides are submitted to an albuminous 
solution, which acts as a mordant to make the color penetrate 
more easily. 

The leather is dyed black or red, but the latter color is most 
used. 

The dye is made of a decoction of sandal or Sanders wood, 
the quantity of which must be judged by the operator, who 
obtains the correct shade by repeated essays on small fragments 
of leather. 

Sandal or Sanders wood and cochineal give a richer color, 
and are sometimes used. 

The leather must be dyed in several coats, taking care that 
the preceding one is well dried before applying another coat, 
the dye being applied with a brush to the grain side. 

After dyeing, the leather is again impregnated with a mixture 
31 



482 THE MANUFACTURE OF LEATHER. 

of birch oil and seal oil, which must be made to penetrate as 
much as possible, by rubbing energetically with a flannel rag 
on the grain side. 

As a mordant in Russia they use chloride of tin prepared in 
the following manner : Take 5 ^ ounces of nitric acid, heat it 
very slowly under a chimney having a good draft so as not to 
be affected by the emanations of the acid, pour in this hot 
solution, stirring it meanwhile with a glass or a wooden stick, 
1 pound and 2 ounces of salt of tin. This operation must be 
done in the open air or under the influence of a strong draft, so 
as not to inhale the deleterious vapors of the nitric acid, which 
are excessively dangerous. 

Stirring must be continued with caution so as to allow the 
unwholesome vapors to escape ; when the mixture begins to 
whiten add 4^ ounces of fuming hydrochloric acid, stirring 
carefully for a few moments. 

The liquor must be cooled and put in hermetically closed 
bottles, to be kept in a cool place, and before using this liquor 
it must be diluted in a volume of from 15 to 20 times its own 
weight of pure water. 

The leather being prepared and cleansed from all foreign 
substances, the mordant is applied very briskly and uniformly 
with a brush. 

As coloring matter in Russia they use 1 lb. 2 ozs. of sandal 
or Sanders wood boiled for an hour in.i y§ gallons of pure water. 
This liquor is filtered and 1 ounce of prepared tartar and soda 
dissolved in it. 

This mixture is boiled for an hour, and it is left standing for 
a few days before using, as it is then stronger. 

The sides destined for black dyeing are only oiled on the 
flesh side, which must be dried with a woolen rag, leaving the 
grain half moist, and irreproachably neat. 

The leather is submitted two or three times to the mordant, 
according to its thickness, and then dyed as many times with 
the warm dye, the temperature of which must be raised if nec- 
essary; i. e., the dye must only be applied while warm, and if 



RUSSIA LEATHER. 483 

the operation takes too much time according to the number of 
skins, the dye must be kept at the proper temperature. 

The application of the mordant and dye is done with a brush 
by rapidly spreading the liquid which is poured on the leather. 

Rapidity in this operation is necessary in order to spread the 
dye equally on the whole surface of the leather and to insure 
the same shade on all its parts. 

The first coat of color is applied immediately after the mor- 
dant and while the leather still retains some of its moisture ; the 
dye in this manner taking more easily and there being less risk 
of shading. 

It is desirable for the good execution of this work to have 
two men operating together ; the first applying the mordant, 
and the second the color immediately afterward. Should the 
color not be uniform another coat is applied at once with a 
lighter solution. 

This red color lasts as long as the leather itself and does not 
damage it, whatever may be the time of its stay in the ware- 
house. 

After the application of the dye the leather must be slightly 
moistened on the flesh side with some tan juice and dried, and 
then grained. 

The red Russia leather acquires a brilliant appearance when 
its colored side has been coated with gum tragacanth solution 
by means of a sponge ; this gelatinous water must neither be 
too thick nor be applied in too large a quantity. 

For graining the hides the same methods are followed as for 
the manufacture of Morocco leather; but instead of being 
"straight grained'.' or "pebbled" the finish is a diamond- 
shaped grain. 

A graining machine, especially for Russia leather, was in- 
vented by Towein, who, unfortunately, died when he was finish- 
ing it. 

However, his work survives him, and his graining machine 
is in use in large French establishments and its success is com- 
plete. 



484 THE MANUFACTURE OF LEATHER. 

Black colored Russia leather is prepared in the same manner 
as has been described, but is stained by the application of ace- 
tate of iron, aniline and other blacks being also used. 

MANUFACTURE OF BIRCH OIL. 

This oil is commonly called Russia oil, but, notwithstanding 
this name, the bark of the birch tree of all countries will pro- 
duce it, and it is in the whitish, membranous epidermis of the 
bark that the oil exists, and this should be carefully separated 
from the ligneous or woody matter. 

The bark is considered preferable when it has been freshly 
gathered. 

If the distillation of the oil is done in the spring, some birch 
buds are mixed with the bark ; a more limpid oil is thus ob- 
tained and its odor is more penetrating and delicate, resemb- 
ling a little the flavor of the rose. This mixture also facili- 
tates the separation of the oil, which when thus prepared is of 
a lighter color, from the very small quantity of soot it contains. 

Many systems are followed to distill the birch oil ; some of 
them, very simple, are within the capabilities of any one ; the 
others, more elaborate, require the science and complicated 
stills of the chemist. This oil can be readily obtained by dis- 
tilling the bark in iron cylinders placed horizontally in a furnace. 

In each of the methods of distillation, to be hereafter de- 
scribed, separate the birch oil from the tar, acid, etc., under- 
lying it, and keep it in a glass-stoppered bottle or some other 
close vessel. 

The following is a simple method for distilling this oil: 
Above any kind of receiver place an earthen pot of a conveni- 
ent capacity with a hole pierced through its bottom ; fill the 
pot with the bark, put fire to the bark, and cover the earthen 
vessel with another of similar capacity, also having a hole in 
its bottom. The bark burns slowly, the smoke and the hetero- 
geneous products of this kind of distillation evaporate through 
the aperture in the upper vessel, and the oil runs through the 
lower opening into the receiver below. 



RUSSIA LEATHER. 



4 8 5 



Another method, which is that of Fischerstroem, is a little 
different from this, although based on the same principles. To 
carry it out, fill an iron caldron with bark and cover with a 
convex lid, in the middle of which a hole is made, for the intro- 
duction of an iron tube ; above this caldron another one is 
placed and the two secured together, the second caldron hav- 
ing a hole in the bottom, through which passes the iron tube of 
the first caldron, but which must not touch its bottom. 

The two caldrons, suitably united, must be hermetically 
closed by means of clay. They are then inverted and half 
buried in the ground, the one containing the bark being upper- 
most, and it is daubed over with a 
mixture of sand and clay. A large 
wood fire is built around this iron 
caldron, so as to bring it to a white 
heat. When everything is cooled 
the distillation is complete and the 
caldrons may be opened. 

In the upper caldron there will 
be a fine coal powder, and in the 
other the products of the distilla- 
tion, i. e., the birch oil floating, 
underlaid with a little tar, upon a 
slight layer of pyroligneous acid. 

By Grouvelle and Duval-Duval's 
process, the material is introduced 
into a copper still, similar to those 
used to distill wood in the manu- 
facture of acetic acid. The receiver is so adapted as to be im- 
mersed in water in which the gaseous products are condensed, 
and, as in the manufacture of acetic acid, the resulting pro- 
ducts are pyroligneous acid, tar in larger quantity, and the oil 
more colored, and less abundant. 

The oil may be obtained nearly colorless by rectification, but 
this is not necessary, unless the oil is intended to be employed 
on delicately colored leather. 




486 THE MANUFACTURE OF LEATHER. 

By repeating the distillation per descensum, Payen ascertained 
that with a simple apparatus it is possible to obtain an oil less 
colored and in the proportion of one-fifth more, at a tempera- 
ture less elevated. 

To construct this apparatus, which is shown in Fig. 125, a 
hole is made in the bottom of an earthen furnace A, large 
enough to receive the neck of a matrass M. The furnace is 
supported by two bricks placed upon the plank, which is also 
perforated so as to admit of the passage of the neck of the 
matrass, and which rests upon the trestles C, C. The matrass 
is filled to its utmost capacity with the epidermis of birch bark ; 
it is inverted and passed through the furnace and the board. 
Then the neck is luted and placed in the position seen in the 
figure, being supported by sand thrown into the bottom of the 
furnace as high as F, F, and in order to expose the matrass to a 
uniform heat, it is protected by inverting over it an earthen 
hemispherical vessel or crucible. Around this, burning coals 
are placed, and the fire is kept up through two lateral openings, 
D, D, the dome /, K, L being placed upon the furnace top. 
Condensed water first trickles from the mouth of the matrass 
into a vessel placed beneath, and this is succeeded by drops, 
and then by a constant stream of an amber-colored oil. After 
a time this ceases, and it is necessary to apply heat lower down 
to the neck of the matrass, so as to cause the discharge of the 
last portions of all tarry matters which have condensed in it. 

The products obtained by the distillation of one hundred 
parts are as follows : 

A brown, oily matter, light fluid empyreumatic, soluble in ether. 70.00 

Thick dark-brown tar, containing a little oil 5.00 

Water acidulated with pyroligneous acid 10.00 

Light spongy charcoal 12.50 

Gases 2.50 

100.00 
BIRCH OIL AND LEATHER. 

Birch oil is obtained by dry distillation, and the process by 
which the Russian peasants effect the operation is the most 



RUSSIA LEATHER. 487 

simple that can be imagined. A caldron capable of being 
hermetically closed, set in a brick fire-place above the ground, 
is connected, by means of a pipe, with another caldron buried in 
the ground. That is the whole of the apparatus. The upper ap- 
paratus is filled with dry birch bark, closed up, and then heated. 
The vapor which the enclosed bark gives off finds its way to the 
buried caldron, is there condensed, and becomes a dark-brown 
liquid. This is birch-tar. The tar is allowed to get quite cool, 
and during this process there rises to the surface a vegetable 
acid contained in the tar, which must be skimmed off. On the 
tar being distilled, an oil with a peculiar smell, something like 
that of cedar -wood, is formed, and it is this which imparts to 
Russia leather its peculiar odor. 

Birch-tar, however, obtained in the way described, contains, 
besides the oil just alluded to, other oils, which possess a rather 
unpleasant empyreumatic smell. The raw birch oil of com- 
merce, therefore, gives out this smell of burning to a very much 
greater extent than it does the pleasant smell, and persons not 
aware of this fact will not recognize birch oil as Russia oil, and 
will not risk applying it to their leather. These oils possessing 
this empyreumatic smell, however, are very volatile, and when the 
birch-tar is spread upon the leather they soon evaporate, merely 
from coming in contact with the air. When this is effected, only 
the pleasant-smelling oil remains, and the well-known grateful 
odor of the Russia leather is secured. It may be asked, "Why 
cannot the oils with the burning smell be removed without wait- 
ing for them to evaporate after being spread upon the leather?" 
It is possible to effect this by a special treatment, but as the 
process is a very costly one, and as only a relatively small quan- 
tity of the pure oil is obtainable from the birch-tar, the price 
of the pure oil would be very high. Birch oil is a thick and 
almost black fluid, and is consequently only suitable for the 
smearing of black leather. The oil distilled from it — birch-tar 
oil — is a thin liquid, and although not much lighter in color 
than the oil, it is transparent. 



488 THE MANUFACTURE OF LEATHER. 

RUSSIA ODOR TO CALF LEATHER. 

To impart the Russian odor to calf leather, the skins should 
be tanned in the ordinary way with oak bark, and then well 
washed and all the water got out of them, after which the grain 
surface should be lightly brushed over with a mixture made as 
follows : 60 per cent, of bright fish oil, and 40 per cent, of the 
thin liquid birch-tar oil. Let the skins then dry, and the de- 
sired object is attained. 

BIRCH-TAR AND PINE-TAR THEIR DIFFERENTIATION. 

It is frequently very essential to know for a certainty the 
sources of tar. The subject has been investigated by Hirschsohn, 
who recommends the following process for the differentiation 
of birch-tar and fir-tar. At 68° F. birch-tar has a specific 
gravity of 0.925 to 0.945 ; while pine (fir) tar, at the same tem- 
perature, is 1.02 to 1.05 ; the one floating in water, while the 
other will sink if entirely freed of air. Birch-tar agitated with 
10 volumes of water, abandons none of its coloring matter, 
though the water, while remaining perfectly colorless, acquires 
a markedly acid reaction. The addition of perchloride of iron 
to the water, produces a green color reaction. If 2 drops of 
anilin and 4 drops of hydrochloric acid be added to 5 ccm. of 
the water, a yellow color reaction results. If 1 volume of birch- 
tar be agitated with 20 volumes of petroleum- ether and filtered, 
a clear, brownish-yellow liquid is obtained, which does not be- 
come green when agitated with a diluted solution of copper 
acetate. 

The aqueous extract of fir-tar is, on the contrary, colored a 
marked yellow, is of acid reaction, but becomes red on the 
addition of FeCl 2 (instead of green). Treated with anilin and 
HC1, the color passes to red. The petroleum solution, agitated 
with copper, becomes green. Finally, when pine (fir) tar and 
alcohol are agitated together, the former takes up no color. 
If there is any muddiness, or even cloudiness, you may be 
certain that the tar is contaminated with birch-tar, kerosene 
products, coal-tar, etc. 



CHAPTER XXXIV. 

WEIGHTING OF LEATHER. 

No advances worthy of note have of late been made in the 
art of weighting leather. The same old methods are still in 
vogue, and apparently give full satisfaction. Weighting with 
sugar is by far the most common. 

In testing leather which has been weighted with sugar, it is 
usual for the analyst to specify only the percentage of sugar or 
glucose found, and this particular percentage is then considered 
as indicating the artificially added weight. Recent analyses 
have, however, proved that this is no criterion. 

The presence of sugar or other soluble matter is first of all 
indicated by the heavy shrinkage which occurs in washing out 
a sample of leather thus weighted. If the loss is insignificant 
or normal it may be taken for granted that the leather has not 
been tampered with. Artificial weighting is a tedious process, 
and the manufacturer employing such methods at all is sure to 
do his work thoroughly. 

A sample of sole leather was recently analyzed which showed 
a washing-out shrinkage of no less than 16.8 per cent. So heavy 
a loss naturally presupposed the presence of artificial weighting 
matter in considerable proportions. Further analysis showed 
that only 5.73 per cent, of the matter thus lost was sugar, and 
that 10.3 per cent, of the total loss consisted of other matter, 
which is in itself a very high percentage for sole leather. The 
residue on being subjected to other tests to determine the 
presence of tanning matter, etc., developed so large a percent- 
age of foreign non-tanning substance as to utterly preclude the 
possibility of the latter owing its origin in entirety to the tan- 
ning materials employed. The nature of the non-tanning 

(489) 



490 THE MANUFACTURE OF LEATHER. 

matter present could not be accurately determined, but it 
seemed to be of vegetable origin. The excessive presence of 
non-tanning matter may be attributed to the fact that in this 
instance, as in all probability is most often the case, the tanner 
had used molasses for weighting with, instead of a solution 
specially prepared by himself, the former being far cheaper, as 
well as handier. Molasses consists of about 50 per cent, sugar, 
30 per cent, non-saccharine matter (organic and inorganic), and 
20 per cent, water. According to this estimate, the presence 
of 5.7 per cent, of sugar, as in the instance referred to above, 
would represent a weighting with about 9.2 per cent, molasses 
(free from water). 

This would leave of the 16.8 per cent, total shrinkage, a fur- 
ther loss of 7.6 per cent, or a figure just within the legitimate 
bounds of washing-out loss for sole leather. 

We may thus conclude that, given the percentage of sugar 
in analyzing a weighted leather, if the washing-out loss still re- 
mains very high after deducting the former, the actual weight- 
ing can be fairly estimated at one and one-half times the 
weight of the sugar found. 



CHAPTER XXXV. 

TANNING AND DYEING FURS AND HAIR-SKINS. 

THE hair is thicker in the autumn, and by beginning work at 
that time of the year the skins will be ready for market when 
the demand is at its best. 

TANNING CALFSKINS. 

In tanning calfskins in the hair, the tannin acts from the flesh 
side only and the hair will consequently be apt to slip until the 
tan reaches the hair follicles. All unnecessary handling should 
therefore be avoided, and the actual tanning be done as rapidly 
as possible, so as to give the hair no chance to fall out. 

The skin must of course undergo a preliminary thorough 
cleansing, etc., and as the usual method of soaking, liming, etc., 
cannot be employed, the tanner must resort to special proces- 
ses. Without some kind of preparation, the tanning would be 
a very slow operation and the skin be very apt to come out 
hard and tinny. 

Only perfectly sound and fresh skins can, needless to say, be 
used. To remove all impurities the skins are first soaked in 
fresh, clear water as cold as the work admits of, and the water 
frequently changed. It is best to use covered vats — of stone- 
ware or cement for preference, as these best retain the required 
low temperature. Soaking in running water is not to be re- 
commended, as the action is less even and the skins are apt to 
accumulate slime and other impurities which make the hair 
slip. 

After soaking one day, the skins are thoroughly worked on 
flesh side, to remove blood, superfluous flesh, etc. As this 
operation has to replace shaving, etc., it must be attended to 
very thoroughly, and specially heavy parts, as, for instance, the 

(490 



492 THE MANUFACTURE OF LEATHER. 

pate, are either cut out or rolled to same thickness as rest of 
skin, which is an operation requiring some experience. 

Next, place in fresh water, turning often ; finally work and 
rinse again. 

The skins are now ready for plumping. For this purpose 
they are soaked in a weak solution of sulphuric acid until suffi- 
ciently swelled (a cut will then show transparent instead of 
white). Then rinse again in fresh water and place in soda bath 
(5 to 6 pounds to enough water for 10 skins). This is done 
to reduce the swelling and to neutralize acidity. The soda is 
then removed by repeated rinsing and by finally being passed 
through water to which a little muriatic acid has been added. 

Rinse for last time and place in water containing wheat flour 
2^ pounds per 105 quarts of clean water. This removes last 
trace of acidity and makes the skins soft and pliable. They 
are now ready for tanning. 

As before stated, the tanning should be done as rapidly as 
possible. The strength of the tanning liquor is therefore grad- 
ually but not too slowly increased by adding extracts. As 
soon as the tan has taken hold thoroughly, a fairly strong liquor 
may be used, especially as in the case of skins tanned in the 
hair, a soft grain surface is of slight importance. 

A mixture of hemlock and quebracho extracts may be re- 
commended. Both make a soft tannage and supplement each 
other. The skins must be thoroughly tanned, or the grain is 
apt to be hard and peel off. 

When thoroughly tanned, and not before, the skins are well 
fleshed to remove last particles of flesh, etc., which might inter- 
fere with the stuffing. The latter can, of course, only be done 
from the flesh side. 

First, rinse well ; wash the hair side thoroughly in warm 
soapsuds and dry in open air. The stuffing is applied warm 
and at frequent intervals. When the grease is completely ab- 
sorbed, grain, stuff lightly again and dry out. 

The skins are lastly slicked off, beaten and brushed out. The 
finish may be improved upon by waxing on flesh side. 



TANNING AND DYEING FURS AND HAIR-SKINS. 493 

FOR TANNING FURS, PELTRIES AND DEER SKINS. 

(1) All skins, whether for furs, other peltries, or leather, 
must be thoroughly freed from flesh, fat and foreign materials. 
To do this beam with a knife, or scraper, and then scour well 
in suds of fine soap and sal soda, before any tan stuff or color- 
ing matter is applied. Care should be exercised to see that 
the pelt is perfectly free from suds, by rinsing and wringing ; 
also, by beaming previous to tanning. 

(2) When the pelt is well cleaned and scoured, as above di- 
rected, make brine of common salt at blood heat until no more 
will dissolve. Then prepare a like quantity of mucilage, by 
passing very warm water through a fine sack filled with clean 
wheat bran. Also, dissolve a small quantity of good starch in 
warm water. Let the brine, mucilage and starch-water settle 
till quite clear, then pour them carefully together into a wooden 
or earthen vessel of sufficient dimensions to give free motion to 
the pelts when stirred. Place the vessel where it will keep 
warm for two hours. 

(3) Dip the pelts in clean, strong alum water, at blood heat, 
for two hours ; rinse the pelts free from the alum water, and 
wring or beam them as dry as possible. 

(4) When all is ready, pour into a mixture of brine and mu- 
cilage (still keep warm). Add a quantity of sulphuric acid 
(oil of vitriol), two pounds of acid to ten gallons of water or 
mixture, and put the pelts in quickly, stirring them as briskly as 
possible for a few minutes. Take out the pelts, and scrape 
flesh as clean and dry as possible, putting back in same process 
for one hour. Be careful to have the mixture touch every part 
of each pelt. 

(5) Let the pelts hang in a shady, airy place, until just dry 
enough to turn white when pulled or stretched in any direction. 
Continue the pulling and working of each pelt, changing the 
pelt round as it is pulled, to keep the fiber subject to an even 
effect. Much depends upon working the pelts at the right 
time; that is, when just dry enough to turn white when pulled, 
and by continuing the process of working until fully dry. 



494 THE MANUFACTURE OF LEATHER. 

(6) When the pelts are quite dry they should be beamed 
over a beam, with a dull beaming knife, and finished by polish- 
ing the flesh side with coarse sandpaper. 

IN THE PROCESS OF COLD TAN. 

( 1 ) Care should be taken to clean the pelts free from all for- 
eign substances, after which place them in strong liquor made 
of alum and salt. This is to set the fur. Take out and beam 
well, then place in tan liquor made as above. Stir often. Thick 
skins, such as cow hides for robes, should remain from two to 
four days, according to thickness. 

(2) All pelts should be cut down even with the currying 
knife before placing in tan. Furs, large and small, should be 
milled in sawdust. They are best handled in a fur worker run 
by power; this takes out all remaining oil left in the fur. 

DYEING FUR SKINS. 

Most tanners are no doubt at some time or other called upon 
to tan the skins of fur-bearing animals of the most diverse 
character, says the Schuh und Leder of Berlin. The actual 
tanning process is well-known to all, and the conscientious tan- 
ner fulfills this part of his commission to the best of his ability, 
although the result often leaves much to be desired. The main 
object, from his point of view, is to see that the hair is properly 
set, and this is usually accomplished by the use of alum ; the 
appearance of the fur is often looked upon as a matter of 
secondary importance. By allowing the hair to retain its 
natural color, as is generally done, the commercial value of 
many varieties of peltry is less than it might be made if suitably 
dyed ; in fact, in some instances, where skins from the same 
species of animal possess fur of totally different color, as they 
sometimes do, it is essential, in order to secure an even appear- 
ance, that the pelts should be dyed uniformly, thus enhancing 
their beauty and market value considerably, without in any 
manner detracting from the quality. 

The dyeing of fur skins is a distinct branch of the furriers' 



TANNING AND DYEING FURS AND HAIR- SKINS. 495 

trade, and as the skin itself will not stand a heat of more than 
104 F., the dyeing process is a very delicate operation, 
the trade secrets of which are more jealously guarded than 
those of almost any other. Where the whole skin is to be 
dyed, the dipping process is resorted to, while, where it is de 
sired to color only the lighter portions, or to darken the tips of 
the hair, brushes are used to apply the mordant and coloring 
matter, the stiffness of the bristles used depending on the depth 
to which it is desired that the color shall penetrate. Suitable 
brushes are also used to produce stripes or other peculiar 
markings, and as coloring materials : burnt gallnuts, sulphate 
of iron, verdigris, sulphate of copper, etc. By means of these, 
all the shades of gray can be produced, as also a scale of tints, 
ranging from the lightest brown to the most intense shade of 
black. 

Of late the manufacture of tar-colors, which has revolution- 
ized the dyeing trade generally, has, in connection with the 
newly introduced so-called ursol-colors, opened up a new field 
for the fur dyeing industry, especially as no particular skill as 
a dyer is required in using ursol colors ; any tanner can, by 
giving the matter some attention, arrive at very satisfactory re- 
sults. 

As inquiries are often received from tanners as to the dyeing 
of fur skins, we take pleasure in placing before our readers 
herewith some of the latest developments in this field of in- 
dustry, taken from the detailed results of a series of experi- 
ments with ursol colors made by two well-known German ex- 
perts, the accuracy of whose observations have been personally 
verified by us. The account in question appeared in issues 
Nos. 13 and 17 of the Faerber Zeitung. 

Ursol colors are manufactured by the Aktien-Gesellschaft fur 
Anilin-Fabrikation in Berlin under the trade marks : Ursol D, 
Ursol P, Ursol C and Ursol DB. Of these D produces a dark 
brown and black, P a reddish-brown, C a yellowish-brown, and 
DB is specially adapted for bringing out a bluish or intense 
black. A large variety of shades can also be obtained by 
judicious blending of the various grades. 



496 THE MANUFACTURE OF LEATHER. 

Before a skin can be colored it must first be tanned and pre- 
pared, and all grease removed from the hair so as to make it 
susceptible to the dye. The latter process is technically desig- 
nated as "killing the skin," and if properly performed, does 
not rob the fur of its elasticity or injure the skin. Cold liquors 
must only be used in degreasing. 

Among the methods employed for "killing the skin," the 
lime process is the one giving the most satisfactory results. It 
consists of treating with a degreasing liquid prepared in the 
following manner : Dissolve in two litres hot water 60 grammes 
powdered sal-ammoniac and 15 grammes aluminium sulphate, 
and add to this, stirring briskly, a milk of lime made by dis- 
solving 200 grammes unslaked lime in four litres of water. 

The resulting solution, which should be kept in well-covered 
stone jars, and should be stirred well before using, is applied 
with a brush on the fur side one or more times, according to 
how thorough a cleaning is necessary, and the skin is then 
placed to dry in the shade, in a not too warm place ; if dried 
too rapidly, the hair loses its elasticity and the skin becomes 
hard. 

When dry, the lime dust is removed by beating and brush- 
ing, and the skin is then ready for the (ursol) dye bath, 
although, if first treated with a mordant of bichromate of potas- 
sium and cream of tartar, a saving of dye will be effected, as 
well as the process of oxidation facilitated. Sulphate of iron 
or sulphate of copper may also be used as mordants when the 
skins are to be dyed black. 

By replenishing with fresh potassium bichromate and cream 
of tartar in quantities equal to one-third of the original propor- 
tions, the bichromate bath may be used again ; but after the 
same bath has served twice, or at the most three times, it is ad- 
visable to replace it by an entirely fresh solution. 

After mordanting, the skins are rinsed and placed in the dye 
liquor, and, to insure a uniform color, care should previously 
have been taken to work them evenly and thoroughly in the 
bichromate solution, stress being laid on the point that they 
must always be handled fur-side down. 



TANNING AND DYEING FURS AND HAIR-SKINS. 497 

The method of dyeing will be best understood by a detailed 
description of a few representative examples. 

For instance, rabbitskins may be dyed a brilliant golden 
brown in the following manner : The skins are cleansed thor- 
oughly in a bath made up of about 10 grammes soap and 10 
grammes ammonia to 10 litres of water, in which they are al- 
lowed to remain from 1 to 2 hours, during which time they are 
handled repeatedly; then taken out and rinsed thoroughly. 
They are next soaked for about 12 hours in a mordanting 
liquid of 20 grammes potassium bichromate and 10 grammes 
cream of tartar to every 10 litres of water; then removed and 
rinsed, and placed in the dye liquor, which consists of 6 
grammes Ursol P to every 10 litres of water. After 10 hours' 
immersion, the fur will have taken on the desired color. 

Goatskins (Angora) are dyed a medium yellowish-brown 
as follows — Mordant : 20 grammes potassium bichromate and 
10 grammes cream of tartar per 10 litres water (time of im- 
mersion 12 hours). Rinse well and dye out with 10 grammes 
of Ursol P and 1 pint peroxide of hydrogen to 10 litres of 
water. Six hours is required for this process. 

Ursol D, used alone, produces grey ; with a bichromate mor- 
dant, violet shades, and if used in more concentrated form, 
black. 

A beautiful dark brown for Thibet or wild goat is obtained 
as follows : Mordant : 40 grammes potassium bichromate and 
20 grammes cream of tartar to 10 litres of water (12 hours) ; 
rinse well and dye for 24 hours in a bath made up of follow- 
ing proportions : 5 grammes Ursol D, 5 grammes pyrogallic 
acid, 300 grammes peroxide of hydrogen ; 20 grammes am- 
monia, 10 litres water. If more rapid action is desired, a 
stronger dye liquor is used, viz., 20 grammes Ursol D, 10 
grammes pyrogallic acid, 750 grammes peroxide of hydrogen, 
20 grammes ammonia, 10 litres water. With the latter form- 
ula, the time required for dyeing is reduced to 1 ]/ 2 hours. 

A grey-brown for wild goat is produced by mordanting with 
bichromate — cream of tartar and dyeing out with : Ursol D, 1 
32 



498 THE MANUFACTURE OF LEATHER. 

gramme; Ursol P, i gramme; pyrogallic acid, I gramme; per- 
oxide of hydrogen, ioo grammes; ammonia, 10 grammes; 
water, 10 litres. Leave in dye liquor 12 hours. 

Light brown for long-haired musk-ox : A solution, per litre 
of water, of Ursol P, 10 grammes ; Ursol D, 8 grammes ; pyro- 
gallic acid, 10 grammes; peroxide of hydrogen, 100 grammes, 
and ammonia, 8 grammes, is made by first adding the two 
Ursols in a heated state ; then the peroxide of hydrogen and 
pyrogallic acid, and lastly, when all the other ingredients have 
been incorporated, the ammonia. No mordanting is necessary, 
and the dye is applied with a brush and allowed to dry. 

Imitation of seal-skin in clipped musk-ox : For mordant, use, 
as heretofore, potassium bichromate and cream of tartar, and 
color with a solution of 8 grammes Ursol P, 6 grammes 
Ursol D, 5 grammes pyrogallic acid, 125 grammes peroxide 
of hydrogen, and 5 grammes ammonia to 1 litre water. When 
dry, clean thoroughly, and apply with a brush to the tips of 
the hair a dye of 10 grammes Ursol D and 250 grammes per- 
oxide of hydrogen to 1 litre of water. In about an hour the 
tips of the fur will show black and a strikingly deceptive imi- 
tation of seal-skin is the result. 

Imitation nutria in clipped rabbit : Apply with a brush, a 
solution of 12 grammes Ursol P, 8 grammes Ursol D, 6 
grammes pyrogallic acid and 100 grammes peroxide of hydro- 
gen, to 1 litre of water. r 

Intense black for Angora goat or other similar skins : Mor- 
dant with 20 to 30 grammes potassium bichromate, and 10 to 
15 grammes cream of tartar to 10 litres water ( 12 hours). The 
use of a more powerful mordant is not advisable, as it imparts 
a brownish tinge to the black. Rinse well and dye out with : 
30 grammes Ursol D, 1 litre peroxide of hydrogen, in 10 litres 
of water. Twelve hours will bring out the desired color. A like 
proportion of sulphate of iron or sulphate of copper may be 
substituted for the potassium bichromate in the mordanting 
liquor, and the former will also be found very effective. 

Ursol DB is especially useful in producing a blue-black tinge, 



TANNING AND DYEING FURS AND HAIR-SKINS. 499 

but in this case the potassium bichromate mordant must be re- 
placed by one of sulpate of iron and cream of tartar, or sulphate 
of copper and cream of tartar, or a mixture of the two sulphates 
and cream of tartar, which all give excellent results. 

Directions for producing a blue-black tinge are — Mordants : 
I. 20 grammes sulphate of iron and 10 grammes cream of tar- 
tar to 10 litres water (12 hours) ; II. 20 grammes sulphate of 
copper and 10 grammes cream of tartar to 10 litres of water (12 
hours) ; III. 15 grammes sulphate of iron, 5 grammes sulphate 
of copper and 10 grammes cream of tartar to 10 litres water 
(12 hours). Dye out with: 20 grammes Ursol DB and 500 
grammes peroxide of hydrogen to 10 litres water (10 to 12 
hours). 

When mordant I. is used the resulting black has a deep-blue 
tinge, and the skin itself remains a light blue. Mordant II. 
gives an intense black, while the skin also becomes black. By 
using mordant III. the skin remains lighter than is the case in 
either of the foregoing recipes, without, however, interfering 
with the desired tinge of the fur. 

When the dye-bath is to be used over again, its strength may 
be replenished by the addition of a proportion of about 60 per 
cent, of the quantities used in the original liquor. 

A peculiar advantage in dyeing with Ursol colors is their 
great coloring energy, which is especially noticeable when the 
dye is applied with a brush to the tips of the hair, or used to 
give a streaked appearance. For example, a single application 
of a solution of about 15 grammes of Ursol D and 100 grammes 
peroxide of hydrogen to one litre water, will be found sufficient 
to tip a fur with black or to tint lightly. 

The appliances required for practical dyeing by the processes 
above described are : A boiler for heating water, several small 
vats, or sawed-in-half petroleum barrels to contain the mordant- 
ing and dye liquors, some racks on which to hang up the wet 
skins, an airy drying-room capable of being heated in cold 
weather, and finally an arrangement for rinsing, so that fresh 
water for that purpose may always be at hand. After each 



500 THE MANUFACTURE OF LEATHER. 

operation the tubs or vats containing the liquors are covered 
over with wooden lids. 

IMPROVEMENTS RELATING TO THE MANUFACTURE OF ARTIFICIAL FUR, BEAVER 
AND NUTRIA — J. BIERMAN, BERLIN, GERMANY. 

Lamb skins are placed in a soap and water bath and then 
pressed out and brushed with a color solution prepared by dis- 
solving i part by weight of Ursol D (paraphenylene-diamine), 2 
parts by weight of Ursol P (paramidophenol), I part by weight 
of pyrogallol, 50 parts by weight of hydrogen dioxide, and 4 
parts of ammonia in hot water, and diluting to the desired tint 
with cold water. After drying, the hair of the skins is combed 
with a wire comb, and a silky gloss is produced by ironing 
with acid. Beaver and nutria imitations are thus prepared. 

WEIGHTS AND MEASURES USED IN THIS CHAPTER. 

Kilogram (kilo), metric = 2.2046 pounds. 
Liter, " = 1.056 quarts. 

Gram, " =15.432 grains. 



CHAPTER XXXVI. 

TAWING LAMB AND KID SKINS FOR GLOVE LEATHER, 
DYEING, ETC. 

Kid gloves are made principally from lamb and kid skins 
imported from Brazil, France and Germany. They come to 
this country packed in bales containing from 250 to 400 skins. 
In preparing the material for gloves, the skins have to pass 
through a number of processes such as washing, unhairing, pad- 
dling, tanning, staking, coloring, and polishing. The skins, 
which are about four feet in length and about three feet in 
width, are first placed in wooden tubs and thoroughly soaked 
in cold water. From 6co to 800 skins are placed in each tub 
and left to soften for from one to two days, according to the 
season. From the soaking tubs they are placed in a circular 
revolving drum and washed. This drum is about eight feet in 
diameter and about four feet in width and revolves at the rate 
of about sixty revolutions per minute. A number of wooden 
pins connected on the interior of the apparatus shift the skins 
about as it revolves, so that the stream of water which passes 
in at the center of the drum thoroughly saturates and frees 
them from dirt. 

After washing for a quarter of an hour, they are taken out 
and placed in lime pits. These pits are about eight feet in 
depth, eight feet in length, and about five feet in width. From 
800 to 1000 skins are placed in each of these pits and are 
covered with lime and water for about two weeks. The lime 
acts on the pores of the skin, opening them so that the hair can 
be easily removed. The skins are taken from the pits by 
means of long-handled tongs. To take off the excess of lime, 
the skins are paddled. This is performed by placing the skins 

(501) 



502 THE MANUFACTURE OF LEATHER. 

in cold water and running them back and forth over a paddle- 
wheel. This wheel is about three feet in diameter, about six 
feet in length, and travels at the rate of about 40 revolutions 
per minute. After paddling, the hair is removed by spreading 
the skins out over a beam, an operator then scraping off the 
hair by means of an unhairing knife. 

A good workman can unhair about 20 skins per hour. The 
next operation is fleshing. A skin is placed as before over a 
beam, the operator cutting off the particles of flesh adhering to 
the skin, giving it an even thickness, and also trimming off the 
ragged ends. The scraps are sold to glue makers, and the hair 
to plaster and carpet manufacturers. About 20 skins can be 
fleshed per hour. After fleshing the skins are washed again 
in the revolving drum for half an hour, after which they are 
fleshed again to take off the grease. The material is then 
paddled again in warm water, after which the skins are spread 
out again on beams and slated, the process taking off the sur- 
plus dirt and giving them a finish. They are then paddled and 
then drenched in a tub of bran and water. About 800 skins 
are placed in the drench tub at a time, and paddled for 12 
hours, the operation removing the lime and opening the pores 
of the skins. The skins are then put into a revolving drum 
containing a tanning liquor composed of alum, salt, flour, and 
the yolks of eggs. After revolving in this drum for twelve 
hours at the rate of 80 revolutions per minute, the skins are 
taken out and hung up on hooks in a drying room in a temper- 
ature of no° F. for twenty-four hours. 

When the skins are dry, they are dampened with water and 
put into a mill and softened. This mill consists of two per- 
pendicular swinging planks suspended from the ceiling, con- 
nected to the bottom ends of which are large wooden blocks, 
which move back and forth when the apparatus is in motion. 
The dried skins to the number of 50 or more are placed on the 
floor of the mill in front of the blocks, which, as they move 
forward, squeeze and press them together until they become 
soft, after which they are staked. This is performed by draw- 



LAMB AND KID SKINS. 503 

ing the skins back and forth over the edge of a broad steel 
knife, about 18 inches in length and about 8 inches in width. 
After this operation, which also softens the material, they are 
put again into the drying room, after which they are staked 
again, the operation taking off the dried flour, which, sticks to 
the material from the tanning liquid. 

The white skins are then packed away for a few months to 
ripen for working purposes. The skins are then selected out 
for coloring, being first washed in a drum of cold water for 20 
minutes, after which they are placed in a revolving bath of egg 
yolk for twenty-four hours, which softens and makes the stock 
pliable. The skins are then colored. A skin is first slicked 
out smooth on a lead covered table and given a wash of potas- 
sium bichromate and soda ; the solution preparing the skin so 
that it will take the coloring ingredients. The gloves are 
colored in black, drab and tan, iron sulphate being used to pro- 
duce black, zinc sulphate for drab, and sulphate of alum for tan 
color. 

The coloring ingredients are poured on the skins with a cup 
and rubbed with a brush. The skins are then dried and 
staked again, and then polished over a flannel covered wheel. 
The raw skins cost now (August, 1897) from $7 to $9 per 
dozen.* 

BLACK ON GLOVE SKINS. 

771 grains logwood extract and 154 grains fustic extract are 
dissolved in one quart of water; the leather is, at 99 degrees F., 
brushed five times with this liquor. Next 154 grains chromate 
of potash and Jj grains sulphate of copper are dissolved in one 
quart of water, and the leather is brushed twice with this solu- 
tion ; after it has been absorbed, the leather is brushed another 
time with the logwood solution. When half dry, it is to be 
rubbed with aqua ammonia (154 grains per quart of water), 
using a woolen cloth ; it is brushed afterwards with water, and 
then treated with yolk of egg and glycerine. 

* The Scientific American. 



504 THE MANUFACTURE OF LEATHER. 

Another black for glove leather is prepared as follows : In 
two gallons of water heated to 115 or 120 F., dissolve two 
ounces logwood extract and two and a-half drachms of fustic. 
In another vessel dissolve two and a-half drachms bichromate 
of potash and one drachm of sulphate of copper in a pint and 
a-half of water. The first liquor is used to rub into the skin 
several times. The second liquor is the blacking ; after it has 
been applied, another coating of the first liquor is given. 
Finally the leather is washed off with water containing am- 
monia, and finished as usual. For other colors and shades on 
glove leather see Chapter on Dyeing. 



CHAPTER XXXVII. 

TO PUT A GLOSS ON BLACK LEATHER. 

THERE are seven different solutions which may be used for 
putting a handsome and brilliant gloss on black leather, and 
the following are the methods for manufacturing them : 

1. Take ten parts of albumen, and dissolve them in ninety 
parts of water. Blood albumen is, the best. The water may 
be either cold or tepid, but its temperature must never be more 
than 70 F., or the albumen will not dissolve. White of egg 
may also be dissolved in its weight of water. The solution is 
put on by means of a soft sponge. Directly afterward the 
skins must be hung up in a place protected from the dust 
and sun. 

2. A solution of gum-lac. Mix up together in a litre (1^ 
pints) of water, 100 grammes (3}4 ounces) of borax, and 200 
grammes (7 ounces) of gum-lac, and boil until the whole is en- 
tirely dissolved. Then add 200 grammes (7 ounces) of negro- 
sine, and leave it to cool. The solution is put on with a sponge. 

3. Caseine dissolved in ammonia. Take a certain quantity 
of white cheese finely ground and put it with some ammonia 
previously dissolved in a quantity of water of equal weight. 
By means of evaporation a substance is obtained which consti- 
tutes a varnish of uncommon richness. 

4. Algine dissolved in water in the proportion of 12 to 100. 

5. China moss dissolved in water. Boil it for two hours. 

6. A varnish called panclarite, which is made in the follow- 
ing manner: Dissolve 100 grammes (3}4 ounces) of soap of 
rosin and 900 grammes (31^2 ounces) of ordinary glove skin, 
finished off with from 30 to 60 grammes (1.05 to 2.1 ounces) of 
glycerine. When the solution has the appearance of a jelly,. 
spread it over the skin with a sponge. 

( 505 ) 



506 THE MANUFACTURE OF LEATHER. 

7. A liquid composed of the following ingredients : 200 parts 
water, 4 parts potash, 20 parts carnauba wax, 10 parts sugar, 
10 parts rosin, 5 parts glycerine, and 2 parts aniline. Boil the 
mixture for half an hour, and add 200 parts glove gelatine. Let 
it cool and put on with a sponge. 

The above are the seven newest processes for putting a gloss 
on black leather, The processes can be modified so as to in- 
clude glove leather; but as given are for any kind of black 
leather. 



CHAPTER XXXVIII. 

SHEEP LEATHERS. 

Few people realize the importance of the sheepskin industry 
or the number of uses to which sheepskins are put. Last year 
(1896) at Chicago alone there were received 3,406,739 head of 
sheep, of which number 2,932,093 head were slaughtered at the 
packing houses. The skins of these 2,932,093 sheep were dis- 
posed of for various purposes, in fact more than the average 
reader has any idea of. We have been able to obtain a portion 
of the uses for which these skins are suitable, and give them 
herewith as follows : The greatest demand probably comes 
from shoe manufacturers, who use a large number of skins an- 
nually in making up cheap shoes. The linings and uppers of 
thousands of pairs of shoes are made from sheepskins, although 
there is little to say of the wearing quality of shoes whose 
uppers are wholly composed of this class of stock. The sec- 
ond largest demand comes from the manufacturers of gloves 
and mittens. Many a pair of gloves which have been made 
from sheepskins are sold as genuine buckskin gloves, but the 
demand for cheap gloves and mittens makes it" possible for 
manufacturers to palm off the sheepskin glove for something 
better than it really is. 

Next in order comes the demand from the bookbinders, 
who consume large quantities of sheepskins in the binding of 
books. The manufacturers of satchels, hand-bags and pocket- 
books, use very large amounts of skins, in fact, we dare say 
that the bulk of these goods are made from sheep pelts. Even 
the better class of these goods, which are not made wholly 
from pelts, are lined with them. To-day there are less of these 
goods made from sheepskins than formerly, owing to the lib- 

(507) 



508 THE MANUFACTURE OF LEATHER. 

eral use of canvas, which takes the place of these skins. Con- 
tinuing the list we find the following articles are made up wholly 
of the skins from the animal with the " golden hoof: " Saddle- 
pads, harness, boxing gloves, baseball covers, bindings of gun 
cases, gussets in overalls, binding of pockets for street-car con- 
ductors, linings for hats (which takes thousands of skins), bel- 
lows, plasters, children's toys of almost endless variety, imita- 
tion chamois skins, saddletrees in place of rawhide, drum heads, 
slippers, leather clothing, catchers' gloves, heel protectors, 
chair seats and purses. Heavy skins are used for blacksmiths' 
aprons and command a good price for large sizes. Skins that 
have the wool left on are also put to numerous uses, among 
which we mention coats, mats, mittens, gloves, caps, sleigh- 
robes, boot-linings, and long wool dusters. 

The cold sweat process is used in a limited extent in this 
country for unhairing sheepskins in order to keep the wool in 
a clean condition, as it would be destroyed by contact with 
lime or other alkalies. 

Sodium sulphide is an agent which is more largely used for 
unhairing sheepskins. Sodium sulphide, when mixed with the 
lime during the slaking process, enters into chemical combina- 
tion with the lime, forming varous mixed sulphides which have 
a much more energetic action on the skin, dissolving out all 
the keratines, but not swelling the skin to the same extent as 
lime alone; the addition of sodium lessens the time required to 
lime a skin, attacks the hair and weakens it or dissolves it, ac- 
cording to the quantity used. It, however, produces a coarser 
grain on the skin, and at the same time does not take so much 
out as lime does alone. 

Arsenic, if mixed in the same way, also forms sulphides and 
hydrosulphides of lime and arsenic, which also have a more 
energetic action on the skin than lime alone, and produce simi- 
lar results to lime and sulphide of sodium, but give a finer 
grained 1 skin, with more gloss. 

In the tanning of sheepskins it is necessary to remove the 
grease. To remove grease from raw sheepskins, the skins after 



SHEEP LEATHERS. 509 

liming are usually pressed between strong presses, hydraulic or 
otherwise, the skins being sprinkled with sawdust to prevent 
them from slipping. 

For raw skins or limed goods the pressure method appears 
the simplest, and, being very effective, the best. Sheepskins 
for mats with the wool are plastered with fuller's earth or 
whitening on the flesh and put in a hot room, a process very 
effective for this particular purpose. 

The skins are then bated. The object of bating and puring 
skins is, first to remove all lime salts contained therein, and, 
at the same time, to rid the skins of the hair sacs, coriin, albu- 
men etc., and to dissolve out a certain amount of the skin sub- 
stance, rendering the leather softer and more pliable, at the 
same time to partially bring down the substance of the skin, 
which has been unduly swollen by the previous process of 
liming. Many other compounds have been patented as substi- 
tutes for hen or pigeon excrement. 

Among such are sulphuric acid, hydrochloric acid, the Tiffany 
bate, which is composed of glucose and stale cheese, ammonium 
chloride, cresotinic acid, borophenol, etc. In some factories 
some of these have proved very succesful, and are rapidly gain- 
ing in favor. Some experiments have been made with using 
pure cultures of the various bacteria which are found in ordinary 
bates. These can now be bought on a commercial scale. 

The skins are then ready for the tanning process, but their 
treatment here depends upon the kind of leather into which 
they are to be made. 

Some manufacturers wash the skin after bating in warm 
water, softened with borax in the proportion of one pound of 
borax to the 100 gallons, and then flesh them; but as previ- 
ously stated, this depends upon the kind of leather into which 
the skins are to be made. 

The Vaughn Machine Co., Peabody, Mass., build a shaving 
and skiving machine for sheepskins. It is constructed on the 
same principle as their fleshing machine ; but it is especially 
fitted and adapted for this purpose. The machine will shave 



5IO THE MANUFACTURE OF LEATHER. 

the stock either partly or fully tanned, clearly and evenly, and 
without tearing or scratches. The capacity is from ioo to 150 
dozens per day. 

IMITATION CHAMOIS LEATHER, 

Which is remarkable for its soft texture and porous nature, is 
prepared by the action of oil on the raw skin. Chamois 
leather was formerly made from the skins of sheep, calf and 
chamois goat — hence its name. Now, however^he flesh split 
of ordinary sheepskins is used. The skins receive a thorough 
liming, and are then split. The flesh split generally receives a 
still further liming in order to remove the coriin and other sol- 
uble matters from between the fibres. The fleshes are now fre- 
quently subjected to a bating process, and a short bran drench, 
which, at the same time, secures the complete absence of lime. 

After the usual beam work, the skins are pressed or hung 
out to remove surplus water, and while still moist are sprinkled 
with oil on a table and folded in cushions, three or four skins 
together, and are stocked for two or three hours, shaken out, 
and hung up for about an hour to cool and partially dry. 
They are again folded in bundles and stocked for a short time, 
taken out, re-oiled, and again returned to the stocks. This 
process is repeated until the skins lose their original smell of 
lime, and acquire a peculiar mustard-like color, and the water 
which was at first present has been entirely replaced by oil. 

When the oiling is complete, the skins are piled in heaps on 
the floor or in boxes. The oxidation of the oil, which has 
already commenced during the process above described, is 
completed by a process of fermentation in which the skins 
heat very considerably. They must be carefully watched, and 
if the heat rises so high as to endanger the quality of the 
leather, the pile is turned over, the skins being turned out to 
cool, and then put back into pile. When this fermentation 
process ceases and the skins are no longer susceptible of heat- 
ing, they are then treated to remove the surplus oil. This on 
the Continent is done by throwing the skins into hot water, 
and wringing or squeezing out the oil (degras). In England, 



SHEEP LEATHERS. 5 I I 

however, the oil is generally removed by washing the skins 
with soda or potash lye. The partly saponified oil which is 
pressed out is recovered by neutralization with sulphuric acid, 
and forms the sod oil of commerce. 

The finishing process consists of staking during drying to 
retain the softness, and smoothing the flesh on the fluffing 
wheel. They may be bleached by sprinkling with water and 
exposure to the sun, or by treatment with a weak solution of 
permanganate of potash, and subsequently with very dilute 
sulphuric acid, or may be treated with sulphurous acid in gas- 
eous form. (See Chapter XL.) In the United States and on 
the Continent of Europe, the skins, instead of being laid in 
piles to oxidize and ferment, are usually hung up in warm 
rooms. This is much less dangerous, and produces a better 
color. 

WHITE LEATHER. 

Glove kid or calf kid or white sheep leather are all white 
leathers. After the soaking and liming of the skins, which is 
usually done by pasting them on the flesh side with a mixture 
of sodium sulphide or arsenic, they are, after unhairing, thor- 
oughly washed in water, well scudded on the beam to get dirt 
and scud out, trimmed and then pured in a weak pure, about 
one to one and a half pails of paste for 200 skins, sufficient to 
make the water opaque, but not soapy. 

After puring, the skins are again washed and worked on 
both flesh and grain, and are then drenched for from six to ten 
hours. The skins are now ready for tawing. The tawing 
paste consists generally of a mixture of flour, egg yolk or egg 
preparation, alum and salt. This may be done in a drum, or 
may be trodden in by foot, the latter process being the Conti- 
nental one. If the drum is used, care must be taken that the 
skins are not allowed to get too hot in the drum. 

After tawing, they are hung up in a cool place for the 
paste to set, dried in a cool place, and then hung for a few 
weeks to soften and absorb moisture. They are then staked, 
fluffed on the flesh, and are now ready for dyeing or finishing. 



512 THE MANUFACTURE OF LEATHER. 

CAPE SHEEP. 

This class of goods, being of coarse texture, and not used 
for the finest purposes, the ordinary pit process is usually em- 
ployed. The skins are unwooled by the sweating or painting 
process, and then further limed to thoroughly swell the goods. 
After liming, they are fleshed and scudded, may be lightly 
pured and bran-drenched after working on the beam to remove 
bran, scud, etc. 

The goods are now tawed in a paddle or ordinary pits, with 
a liquor made from hemlock or other common bark. The tan- 
ning in paddle lasts from four to ten days, with liquors of con- 
stantly increasing strength ; if in pits, the process takes from 
two to four weeks. The skins are now lightly oiled on the 
grain with fish or linseed oil, damped, staked and re-dried. 

LINING, BINDERS AND SKIVERS. 

The manufacture of sheep-skins into linings, bindings and 
skivers is an important one. The sheep-skins used are both 
•domestic and foreign ; those derived from Great Britain are 
mostly " sheep-skin fleshers/' and are treated with vitriol before 
shipment to preserve them. A flesher is the backside of a 
sheepskin. They are first milled in salt and water, to neutral- 
ize the acid, and are then run out on the beam. 

The materials used for tanning this variety of leather are 
usually hemlock bark, oak wood extract, sumach, gambia, and 
alum. 

These skins are finished in all colors ; hemlock is used for 
colors darker than its own, sumac is employed for white and 
fancy colors, and alum mostly for those that are to be dyed 
black. 

The sheep-skin fleshers are split from the sheep-skins while 
in a state of pelt, and special machines are required for this 
operation. We show in Fig. 126 an exterior view of a sheep- 
skin tannery. 

The processes which we shall first describe are for those 
skins which arrive at the tannery from foreign countries, split, 
free from wool and which are pickled. 



SHEEP LEATHERS. 513 

Sometimes these skins are placed in clean water and washed ; 
but they are not uncommonly removed from the casks in which 
they were shipped and immediately soaked in salt and water, 
worked out on the beam and placed in the tanning liquor, 
whether it be hemlock, sumac, or alum. 

In hemlock and sumac they remain about ten or twelve days, 
the strength of these liquors being gradually increased every 
thirty- six hours, and in alum the skins remain for a much shorter 
time. After being tanned, they are removed from the vats with 
a hook and piled, and left to drain, as shown in Fig. 127. 

The skins are then carried to the drying lofts and each one 
hung upon two hooks, but so placed that the skins do not touch. 

Fig. 128 shows an interior view of a drying loft in a sheep- 
skin tannery, with the skins hanging upon hooks to dry. 

After being dried the skins are removed from the hooks in 
the drying loft, and transferred to the " putting out depart- 
ment," where they are wetted and tacked to boards used for 
putting out. After this operation they are again hung up in 
the loft to dry, and then carried to the "finishing-room" and 
finished on the machines employed for that purpose ; but if they 
are to be dyed, they are carried to the dye-house and colored 
in various hues, aniline colors being generally employed. 

After being dyed, the skins are again hung up in the lofts to 
dry, and are next carried to the finishing department, shown 
in Fig. 129, and rolled, glassed, or pebbled by machines used 
for the purpose, and which have been illustrated and explained 
in detail in Chapter XIX. 

After being finished on the machines, the skins are meas- 
ured, marked and bundled ready for market. 

DRESSING SHEEP-SKIN FLESHERS FOR GLOVE BINDINGS, ETC. 

The following process for dressing "sheep-skin fleshers," to 
be used in the manufacture of gloves, for hidings, etc., was 
patented in 1875, by Richard Hart, of Gloversville, N. Y., the 
patent having, however, now expired. 

The quantity of the mixtures to be specified is intended for 
33 



5H 



THE MANUFACTURE OF LEATHER. 




SHEEP LEATHERS. 



515 




5 i6 



THE MANUFACTURE OF LEATHER. 




SHEEP LEATHERS. 



517 



(n I 




5 l8 THE MANUFACTURE OF LEATHER. 

about two dozen sheep-skin fleshers of the ordinary size. In 
carrying out the process, first immerse, pound, and stir the skins 
for about one-half hour in a fluid mixture, prepared as follows : 
Dissolve one pound of alum in one and a half gallons of water, 
which is readily done by boiling. Then mix in a separate 
vessel, one-half pound each of flour and oatmeal, or one pound 
of either alone, with one gill of oil and one and a half gallons of 
water, and mix this composition with the alum-water. At the 
expiration of the designated time take the skins out of this mix- 
ture and stretch them, and remove the ground work and knife- 
marks from the grain side. Then immerse them for about the 
same length of time, and with the same manipulations as before, 
in a fluid mixture, prepared as follows : One gill of urine, one- 
half bar of bar-soap, one-half ounce of soda, one-half pound of 
salt, and about two ounces of whiting or ochre, all boiled in one 
and a half gallons of water until they are thoroughly dissolved, 
to which are added one-half pound of flour and one-half pound 
of oatmeal, or one pound of either alone, mixed in one and a 
half gallons of cold water. The skins are then dried, stretched, 
and staked out, and can now be faced or finished upon either 
side in the usual manner. 

Instead of urine in the mixture last described, a small quan- 
tity of ammonia may be used, as it produces the same effect ; 
or the proportion of soda may be suitably increased, or lactic 
acid maybe used, and neither urine nor ammonia be employed, 
and still the desired result obtained. 

Skins dressed by the usual method can be finished or faced 
on the flesh side only, and have a rough and hard surface on 
the grain side, besides being rough and stiff in texture. 

Skins dressed by this process, by treatment to both mixtures, 
may be finished on either or both sides, and, it is claimed, are 
made soft, pliable, and with elasticity or " spread" and stronger 
in texture, without becoming rough. 

Skins which are treated to the first mixture only may be at 
once dried, staked, and stretched, and finished on either or both 
sides in the usual manner, without subjecting them to the 



SHEEP LEATHERS. 519 

second mixture, and, it is claimed, will then be better in quality, 
and have a susceptibility of better finish, than skins dressed in 
the ordinary way ; but it is preferable to employ the entire 
process in dressing skins, as they are thus given a superior 
quality and a capacity for higher finish than when the first part 
of the process only is used, and, when finished, bear a close 
resemblance in texture and quality, to deer-skin or castor. 

manasse's method for tawing sheep-skins. 

In 1875 Emanuel Manasse, of Napa, California, patented the 
following process for tawing sheep-skins : 

The skins are taken from the sweat-house, and, after being 
properly treated in the beam-house, are immersed in a solution, 
composed for two hundred skins, of the following ingredients : 

No. 1. Twenty pounds of salt, thirty pounds of white-rock 
potash, three hundred gallons of water. 

The skins remain in this solution for about two hours, and 
are then wrung out dry, and immersed in a solution composed 
as follows : 

No. 2. Twelve pounds of hard soap and two gallons of neat's 
foot oil in one hundred and fifty gallons of water. 

After being kept in this solution long enough to wet them 
through, the skins are removed and hung up to dry, and are 
wet and dried in this manner two or three times. 

After being thus treated and properly tawed, they are put 
in a dry state into clear water, and washed in a thorough man- 
ner to remove all foreign matter from them, and in this moist 
condition are dried to produce leather of various colors, or, if 
a white leather is required, they are allowed to dry without 
further treating. 

The proportions of the ingredients given above may be 
changed, as the nature of the skins requires, without affecting 
the process. 

It is claimed that the skins thus treated combine the qualities 
of softness, pliability, and toughness, which allow the leather to 
be sewed together, as in the manufacture of gloves and like 
articles, without tearing or allowing the stitches to pull out. 



520 THE MANUFACTURE OF LEATHER. 

hibbard's process for preparing and tanning sheepskins. 

Hibbard's process for preparing and tanning sheepskins for 
linings, binders, etc., is as follows : 

To remove the hair, mix the following composition with 
water sufficient to make a thick paste, apply it to the flesh side 
of the hides, fold the skins and keep them at a temperature of 
summer heat. In a few hours they are ready to pull. 

Quicklime (freshly slacked) 3^2 bushel. 

Wood ashes % " 

Salt . . 3 pints. 

For the liming process use the same composition, mixed 
with sufficient water in a vat to immerse the number of skins 
proposed to be limed. One bushel is equivalent to one bushel 
of lime alone. The liming is done at the temperature of 6o° F. 

For tanning six dozen full sized sheep, deer, goat, or similar 
skins, prepare the following composition : 

Salt 18 lbs. 

Sulphuric acid 2 " 

Sumac or quercitron bark 36 " 

Hydrochloric acid 2 ounces. 

Dried clover 18 lbs. 

Water 125 galls. 

Exhaust the sumac or bark by water, add the salt, enough 
to insure perfect solution, then add the acids and incorporate 
by stirring. 

hesthal's process for dressing sheep-skins, etc. 

The following process was patented in 1883, by August 
Hesthal, of San Francisco, Cal., and is useful in the prepara- 
tion of leather for button-pieces, linings, stays, and other small 
articles. 

The process is especially applicable to sheep, lamb, kid, and 
deer-skins. The skins after having passed through the sweat- 
ing process and been properly treated in the beam-house, are 
placed in a solution which we will call No. 1, composed of two 



SHEEP LEATHERS. 521 

pounds of caustic soda, one pound of borax, and sufficient 
water to cover the skins — say one hundred gallons. 

The skins and compound are contained in a suitable drum, 
in which they are run for a half hour and then removed and 
hung up to dry. 

They are then immersed in a solution which we will call 
solution No. 2, composed of five pounds of hard soap, one 
gallon of straits oil, one-half pound caustic soda, and seventy- 
five gallons of water. 

In this solution they remain long enough to become soft and 
wet through, after which they are put into a drum with a part 
of the composition No. 2, and run for about a half hour, being 
then removed and dried as before. 

They are next softened in the composition No. 2, and then 
allowed to drip. 

They are then again placed in the drum with a solution which 
we will call No. 3, and run for about a half hour ; then put back 
into the composition No. 2 and soaked for one hour, and then 
taken out and hung up to dry, after which they are soaked and 
dried in this manner two or three times in composition No. 2 
until they are properly prepared, as some skins may need to 
have this part of the process repeated a greater number of 
times than others. After the skins are treated in this manner 
and have become leather, they are put in a very weak solution 
of composition No. 2, in order to thoroughly soften them, and 
in this wet condition they are dyed in different colors ; or, if 
white leather is required, they are allowed to dry without 
further treating. In this manner is produced a leather which 
is strong and pliable, and when sewed together it does not 
crack, nor do the stitches pull out; and as the skins are pre- 
pared without the employment of lime and sulphuric acid, it 
leaves the fibres in their natural state and strength. 

The proportions of the ingredients given in the above solu- 
tions, Nos. I, 2 and 3, are estimated for about one hundred 
and twenty sheep-skins. 



522 THE MANUFACTURE OF LEATHER. 

COLORING FOR FIVE DOZEN SHEEP SKINS. 
BLUE-REDDISH. 

Preparation of the Skins for the Dye Bath. — Fill a tub with 
15 pailfuls of warm water; to this add 1% lbs. sal soda. After 
it is dissolved, take the five dozen skins and put them in, 
pounding them for five minutes ; then take them out and place 
them in a tub containing 15 pailfuls of warm water, pounding 
them for four minutes. Take skins out, fill a tub with 15 
bucketfuls of cold water, add to the same 1 x / 2 pints oil of 
vitriol ; stir it well ; put the five dozen skins in it and handle 
them for five minutes. This done, withdraw them and place in 
a tub of cold water, letting them remain ten minutes. After 
this, fold them together. 

Dyeing. — Fill a dye-box with ten pailfuls of warm water ; to 
this add 1 oz. blue-reddish aniline, which has been previously 
boiled one minute in half a pail of water and half a tumblerful 
of oil of vitriol. 

To the dye-box add half a tumblerful of oil of vitriol. Put 
one dozen of the folded skins in, handle them very quickly for 
three or four minutes ; then take them out and wash them in 
cold water. For every other dozen add to the box ^ oz. 
blue-reddish aniline and half a tumblerful of oil of vitriol. 
Warm the liquor in the box ; color the rest like the first. 

BLUE-BLUISH. 

The same preparation of the skins for the dye bath as blue- 
reddish. After skins are folded, fill a dye-box with four pail- 
fuls of warm water. Add to the same 1 oz. reddish-brown 
aniline. This must first be added to a half bucketful of water 
and boiled three or four minutes. Put one dozen of the folded 
skins in the dye- box and handle them four times forward and 
back. Then take them out and wash them in cold water. 
For every other dozen warm the liquor up, and add 1 oz. 
reddish-brown aniline. 



SHEEP LEATHERS. 523 

COCHINEAL. 

The same preparation of the skins for the dye bath as blue- 
reddish. Fill a box with three to four pailfuls of milk-warm 
water; add to this 2 ozs. borax, dissolved in 2 quarts boiling 
water. Take 1 dozen folded skins and handle them twice for- 
ward and back ; then take them out, and add for every other 
dozen skins 2 ozs. borax dissolved in half a pailful of boiling 
water. Let the skins remain in the borax over night. Fill a 
vessel with 12 pailfuls of boiled water; add to the same ^ lb. 
turmeric and 2^ lbs. fine ground cochineal. Let this boil 20 
minutes. Add to the same liquor 5 ozs. pearlash and 3 ozs. 
alum, and boil 3 minutes longer. Of the boiled liquor, put in 
a dye-box four pailfuls. Place thirty skins one by one in the 
liquor. After this add two pailfuls of cochineal liquor to this 
dye-box ; put the skins in it and handle them twenty minutes 
forward and back ; then take them out. Color the rest as the 
first. 

LEMON YELLOW. 

Same preparation of the skins for the dye bath as blue- 
reddish. After skins are folded, fill a dye box with four pail- 
fuls of warm water. Add to the same 3 ozs. picric acid dis- 
solved in one-third of a pailful of boiling water. To the same 
box add half a tumblerful of oil of vitriol. Stir it well, bring 
one dozen of the folded skins in and handle them very quickly 
four or five minutes. Take them out and wash in cold water. 
For every other dozen skins warm the liquor in the dye box 
and add to same \ x / 2 ozs. picric acid. Color the rest as the 
first. 

GRASS GREEN. 

Preparation of the Skins for the Dye Bath. — Fill a tub with 
15 pailfuls of warm water, add 1% lbs. sal soda. After it is 
dissolved, take the five dozen skins and pound them five 
minutes ; take them out and fill a tub with 1 5 pailfuls of warm 
water. Put them in and pound them four minutes. Take out 
and put them in a tub of warm water. Let them remain 10 
minutes. After this fold the skins. 



524 THE MANUFACTURE OF LEATHER. 

Dyeing. — Fill a dye box with 4 pailfuls of warm water, add 
to the same 2 ozs. bichromate of potash dissolved in half a pail- 
ful of boiling water. To the box add half a pint chemical blue. 
Stir it well, and put one dozen of the folded skins in it, and 
handle very quickly four or five minutes. Take them out and 
wash them in cold water. For every other dozen skins warm 
the liquor up in the dye box ; add to the same 1 oz. of bichro- 
mate of potash, dissolved in one-third of a pailful boiling water. 
To the box add one-third pint chemical blue. Stir it well and 
color all the skins like the first dozen. 

CLARET OR MAROON. 

Same preparation of the skins for the dye bath as grass 
green. Fill a vessel with 15 pailfuls of water, add to the same 
in a bag 25 lbs. logwood. Let this boil two hours; take the 
bag out. Put in a box 7 pailfuls of warm water, add to same 
1 y 2 lbs. alum dissolved in half a pailful of boiling water. Take 
30 of the folded skins, place them in it, and handle them three 
times forward and back. Take them out, and fill a dye box 
with 7 pailfuls of the boiled logwood liquor. Handle the skins 
four times forward and back, take them out. 

If a darker shade is wanted, add to the same liquor 3 ozs. 
bichromate of potash dissolved in half a pailful of boiling water. 
Handle the skins twice forward and back. After this wash in 
cold water. 

PINK. 

Same preparation of the skins for the dye bath as blue-red- 
dish. After the skins are folded, fill a dye box with four pail- 
fuls of milk-warm water, add to this ^ lb. sal soda, dissolved in 
one-third pailful of boiling water. Handle one dozen of the 
folded skins in it twice forward and back ; take them out, add 
to every dozen skins % lb. sal soda dissolved in half pailful of 
boiling water. After two hours fill a vessel with 10 pailfuls of 
water (after boiling) ; add to same 1 % lbs. cochineal. Let 
this boil 20 minutes, then add to the same 1 % ounces saleratus, 
\y 2 ounces salts of tartar, \yi ounces cream tartar, 2 ounces 



SHEEP LEATHERS. 525 

alum. Let this boil three minutes longer. Take this boiled 
liquor, put three pailfuls in a dye box, and handle 30 skins one 
by one through the liquor. After this add two pailfuls from 
the cochineal liquor, put the skins in, and handle them 15 min- 
utes forward and back, then take them out. Color the rest as 
the first. 

SOLFERINO. 

Same preparation of the skins for the dye-bath as blue-red- 
dish. Fill a dye box with four pailfuls of warm water, add to 
same I oz. fuchsine dissolved in half a pailful of boiling water. 
Take I dozen of the folded skins and handle them very quickly 
three or four minutes. After this, take them out, wash them 
in cold water. For every other dozen skins, warm up the liquor 
in the box, and add to same ]/ 2 oz. fuchsine dissolved in one- 
third of a pailful of boiling water. Put one dozen of the folded 
skins in and handle them three or four minutes. Color the 
rest as the first. 

For the above processes of dyeing sheep skins, we are in- 
debted to "Hides and Leather," of Chicago, and for some 
other matter in this chapter we are indebted to the answers 
made to technological questions by candidates at the examina- 
tions of the City and Guilds of London Institute, as reported 
by the Leather Trades Circular and Review of London. 

DYEING BARK-TANNED SHEEPSKINS INTENSE DULL BLACK. 

In Switzerland they produce an even mat-black on bark- 
tanned sheepskins by washing the skins thoroughly and put- 
ting them in a sumac bath. To 100 skins, according to size 
and weight, they take 20 to 30 pounds of sumac and wheel the 
skins in this bath two or three hours, then wash them out and 
on the table or in the machine press them out, slate them and 
stretch them on frames to dry. To black them they rub them 
over with a strong decoction of logwood with a small addition 
•of aqua ammonia ; this makes them quite dark ; they are then 
colored with a good vinegar black. After the skins are dry 
after the first blacking, they are again rubbed over with log- 
wood and iron black. 



CHAPTER XXXIX. 

ELECTRIC AND OTHER RAPID TANNAGE SYSTEMS. 

The Groth system of rapid tannage by means of electricity 
has, so far, been demonstrated in the United States, at Kansas 
City, Mo., where good results are claimed for it, turning out 
IOO pounds of hides in six weeks without the aid of chemicals, 
extracts, concentrated or heated liquors. Groth's is-no-drum 
system, the ordinary tan pit being all that is required with a 
light wooden frame on it and the electric plant. This system 
we understand has not been a success in Germany, where it has 
been tried on a large scale. L. A. Groth, Stuttgart, Germany, 
is the name and address of the inventor. 

One inventor, E. Worms, Paris, France, claims to hasten the 
tanning process by gradually and moderately heating the hides 
and the liquor within a closed vessel excluding air, and at the 
same time " expelling the water from the cells of the hides by 
electrically decomposing it." The hides are submerged in 
water in a rotating drum, and a tannin extract of 20 B. is run 
in, in the proportion of 50 per cent, of the weight of the hides, 
together with a "vegetable solvent" amounting to " 5 per cent, 
of such weight." The drum is closed and rotated. When the 
temperature has risen to 59 F., an electric current is passed 
through the liquor by means of a suitable circuit, the tempera- 
ture being maintained by its means at yj° to 86° F. When 
the process is half completed the circuit is broken and fresh 
tannin is introduced. Light hides are said to be tanned in 24 
to 48 hours, heavy hides in 60 to 105 hours.' 

Finot, Ward, Gaulard, Meriten, Crosse, Rhodes and others, 
have all invented processes for electric tannage, but we have 
heard no reports of their general employment. 

(526) 



ELECTRIC AND OTHER RAPID TANNAGE SYSTEMS. 52/ 

M. C. Dizer & Co., of East Weymouth, Mass., who operate 
a tannery in conjunction with their shoe factory, are believers 
in quick tannage and are making experiments constantly. 
Douglas M. Easton, who has charge of the tannery, states that 
in the past six months they have tanned by his special 2^- 
hour process, over 200,000 kangaroo skins and 60,000 wax 
calfskins. They are developing with more or less success a 
quick tannage of sole leather, and claim to have made, with 
extract, prime leather in eight hours. They have also been 
experimenting with the chrome process on sole leather, and are 
to build an addition for its practical operation. 

The F. Durio, the Velocitan, and many other processes of 
quick tannage have been before the trade for some time, but 
we have heard little of them as being generally successful. 

Mr. S. Kas, in the Oestereich-Ungarisches Lederblatt writes 
on this subject : " With the various patents for rapid tannage 
which are published almost daily, it is very difficult to judge of 
the real merits, and they should not, as they are, be all consid- 
ered as being one and the same thing. Most of the patents of 
rapid tannage issued lately refer to mineral tannage with 
chrome salts, aluminates, tin and other metallic salts, and are 
almost exclusively employed for the tanning of light small 
skins, such as calf, goat and sheep. Their value does not de- 
pend upon rapidity, for by present methods the tannage is 
rapid enough, but in an improvement in the quality of the 
leather produced. So that when rapid tannage is spoken of 
nowadays, an extra rapid tannage in one, two or three days is 
meant. Of such systems as this there are but few known or 
offered for sale. We refer to rapid tannages for heavy sole, 
harness and belting leather. These systems are few, and of 
these still fewer are of any practical value." 

The past two years have witnessed a notable revolution in 
quick tanning processes. And the revolution has been on 
comparatively new lines. Instead of trying to force tannin into 
the hide, the latest method is to employ chemicals to tho- 
roughly cleanse the hide of all impurities, thus making the 



528 THE MANUFACTURE OF LEATHER. 

texture unusually open and receptive to the tannin. Nor is the 
system followed, of beginning with weak vats and leading up to 
strong liquors. The new scheme means the application of 
strong tan liquors, or extract, to the hides or skins as soon as 
they leave the beam house. Nor are the hides and skins laid 
away. After being fleshed, unhaired and drenched they are 
put in a drum with extract and tanned in a remarkably short 
time. But leathers tanned in this way lack firmness and weight. 

Men who are paying attention to the new quick tanning pro- 
cesses, confidently assert that good sole or harness leather can 
be made in ten hours. They consider thirty hours unusually 
long. The practical tanners who are investigating the promises 
of the new tanning, are hopeful that something has been dis- 
covered whereby the cost of the leather production, particularly 
the commoner sort, will be considerably reduced. By the new 
method, extracts can be used exclusively, and tanneries estab- 
lished in any part of the country, irrespective of the nearness 
of the bark supply. 

Many good processes for rapid tannage have come up, but 
proved too expensive, or had other drawbacks, and were, there- 
fore, neglected. One genius many years ago believed he could 
tan leather rapidly by forcing liquors through the hides by hy- 
draulic pressure. This idea has disappeared in company with 
numerous other fads and notions designed to help tanners, and 
gotten up usually by men who had little or no acquaintance 
with practical tanning. 

Taught by the failure of others, there are companies now 
selling to tanners quick tanning processes that have merit 
enough not only to deserve serious consideration, but to war- 
rant fair trial. The owners of such processes do not make any 
wild claims. Their methods of doing business entitle them to 
attention from enterprising men. 

It will occur to all that, as quick-tanning processes come to 
be better understood and more generally adopted, the some- 
what speculative character of leather manufacturing will be less 
pronounced. Manufacturers of shoes and other leather pro- 



ELECTRIC AND OTHER RAPID TANNAGE SYSTEMS. 529 

ducts have a great advantage over tanners in the fact that a 
comparatively short interval occurs between the purchase of 
their leather and the sale of the goods made therefrom. Tan- 
ners, more especially those making sole, harness, belting leath- 
ers, etc., have to wait from three to six months after soaking a 
batch of hides before the latter are ready for market as finished 
leather. 

The quick-tanning processes on the market to-day are at- 
tracting attention on account of their value and economy. 
Some excellent sole leather is being put on the market regu- 
larly each week in the United States, the tanning of which has 
been accelerated by novel methods. Harness leather of good, 
marketable quality has been made in eighteen days. The time 
required for producing upper leather has been reduced, 
although this is due largely to improved methods discovered 
by the tanners themselves. 

It must be admitted that tanners are somewhat prejudiced 
against testing the merits of new processes. It is doubtful if 
there is a tannery in existence to-day where considerabe money 
has not been sunk in experiments. This of itself should not be 
an insuperable barrier to the introduction of further trials and 
experiments. Regulation of production would be much more 
easily governed if leather could be produced in comparatively 
short time. Less capital would be necessary than at present, 
which is a highly important item. 

Tanners as a body are somewhat suspicious of new processes 
that do not originate in their own plants. Pressure of com- 
petition among themselves, however, is already inducing them 
to look with more favor on new schemes which promise well 
for the making of good leather at reduced cost of production. 
The trouble is that details of new tanning processes, as a rule, 
are so rigidly guarded that tanners feel somewhat nervous 
about agreeing to pay for something about which they are kept 
in the dark. The inventors of rapid processes, on their part, 
would be at the mercy of the tanners if they consented before- 
hand, without promise of pay, to disclose their secrets. On the 
34 



530 THE MANUFACTURE OF LEATHER. 

whole it may be said that while both parties to transactions are 
bound to take fair precautions to protect themselves, there is 
such a thing as too much conservatism, and those who are 
willing to take some chances are more likely to win in the end 
than their less courageous brethren. 

The bark methods of tanning are passing away with great 
rapidity, extracts and chrome are taking their place, and in the 
larger establishments the chemist has become an invaluable 
part of the personnel of the tannery, and he is kept busy making 
investigations and suggestions. 

The old-time tanner has now gone the way of his fathers. 
It is now certain that more advanced methods will be used by 
tanners in general in the near future, or a new and different 
generation of leather producers will step forward to fill the 
places of those now in business. 

The truth is that the average tanner has been too conserva- 
tive for his own interest, but new blood is coming to the front 
and the change will be beneficial. We see this in the way 
modern tanneries and currying shops are being built. They 
are fitted out with all the latest improvements in machinery, 
the various shops and buildings are of brick and iron, with 
cement alleys, not a particle of wood being used in their con- 
struction. All the buildings are of mill construction, thus 
lessening their liability to be destroyed by fire, and saving in 
insurance. 

Electric motors should be used to run all machines, as they 
save fully one-half of the power and thus increase the capacity 
of the plant, as power is developed only when each machine is 
in use. They require no line shafts, no heavy belts, pulleys or 
floor space, the power being conveyed by wire to any part of 
the beam-house, tannery or currying shop. 

Much time is wasted in large tanneries by men running 
backward and forward to carry messages. Here is where the 
telephone is now used in leading tanneries, the yards and 
leach house and other parts of the tannery or currying shop 
being all connected by telephone. 



ELECTRIC AND OTHER RAPID TANNAGE SYSTEMS. 5 3 I 

We only throw out these suggestions to show how rapidly 
we are moving forward, and there can be no stop to our pro- 
gress. The new duty of 1 5 % on hides and calfskins may hurt 
for the moment, but the injury will not be permanent. One 
thing we would like to say to all tanners : never put a dirty 
hide or skin into any kind of tanning liquor; clean it well with 
a mild solution of borax, ij4, pounds to the 100 gallons of 
water. It will pay, and then you will be on the road to'quick 
tannage, as you can then use stronger liquors from the start. 



CHAPTER XL. 

BLEACHING LEATHER; BLUING WHITE LEATHER; BLEACHING 
SKINS WITH THE HAIR ON. 

BLEACHING LEATHER. 

CHAMOIS leather generally possesses a quite pronounced 
yellow color and in this state cannot be dyed delicate shades. 
But even the best quality of kid prepared by the process of 
tawing does not show the pure white color required for the 
production of the most delicate shades of pigeon gray, straw 
color, etc., and hence, in order to obtain the leather absolutely 
white, it will frequently be necessary to subject it, previous to 
dyeing, to a bleaching process. 

Bleaching is mostly effected with sulphurous acid either in 
the form of gas, or as a solution of it in water. Sulphurous 
acid is the product of the combustion of sulphur in the air 
and is the cause of the suffocating odor evolved thereby. 

Formerly leather was bleached by suspending it, in a wet 
state, in a chamber in which were placed vessels containing 
sulphur. The chamber was hermetically closed and kept so 
for twenty-four hours. The gaseous sulphurous acid ascend- 
ing from the burning sulphur dissolved in the water with which 
the leather was saturated and effected the bleaching of the latter. 

This process, though very simple, has the disadvantage of 
the bleaching not turning out uniform, and it is therefore to be 
preferred to effect bleaching by means of a special apparatus, 
or what is still better, to use a solution of sulphurous acid in 
water. For the former purpose various apparatuses have been 
constructed, the general arrangement of which will be under- 
stood from the following description and accompanying illus 
tration : 

(532) 



BLEACHING LEATHER. 



533 



The bleaching chamber (Fig. 130) consists of a small apart- 
ment papered with stout paper and provided with a window 
opening outward, and which can be hermetically closed. In 
the ceiling of the apartment is an aperture which can be 
closed by a slide and communicates with a chimney E. 
Immediately below the ceiling, in another part of the apart- 
ment, is fixed a pipe R which can be closed by a stopper. 
Alongside of this apartment is a brick chamber K provided 
with a hermetically closing door T, and inside with roofing 
tiles arranged in the manner shown in the illustration. This 

Fig. 130. 




chamber communicates with the apartment by an aperture 
above the floor of the latter. 

The leather to be bleached in this apparatus is suspended in 
a wet state upon poles, so that the separate sides are spread 
out flat and do not touch one another. The door and window 
are then hermetically closed, the slide at O is opened, and the 
sulphur in the clay vessel S, which stands in the chamber 
K, ignited. The sulphur- vapor carried along with the sul- 
phurous acid evolved by the combustion of the sulphur is 
condensed on the roofing tiles in the chamber K, and the 
gas thus purified enters the bleaching apartment. The sulphur 
is allowed to burn until a burning match held in front of the 



534 



THE MANUFACTURE OF LEATHER. 



pipe R is extinguished. This pipe, as well as the aperture 
O and the door T is then closed, whereby the burning 
sulphur still remaining in the vessel 5 is immediately ex- 
tinguished. After twelve hours the aperture O as well as 
the doors and windows is opened, the bleached leather is 
taken out and several times washed in water to remove the last 
traces of sulphurous acid. 

BLEACHING WITH SOLUTION OF SULPHUROUS ACID. 

The use of liquid sulphurous acid is far more suitable than 
the preceding process with gaseous sulphurous acid, the 
bleaching turning out much better and more uniform. Fig. 
131 shows the arrangement of the apparatus for the produc- 
tion of the acid required. 

It consists of a brick chamber provided with roofing tiles 
arranged in the same manner as shown in Fig. 130. Into this 
chamber enters a pipe B which is connected with a pair of 

Fig. 131. 




bellows. On the other side of the combustion chamber the 
pipe passes into a forked lead pipe RR which is fixed about 
two inches above the bottom of the shallow wooden vat W, 
and on the lower side is provided with numerous narrow 
apertures. 

The vat W is filled six, or at the utmost, eight inches deep 
with water as cold as possible, and the pipe, which lies in the 
chamber K, is also covered with water. The sulphur in the 
vessel 5 is then ignited, the door of the chamber K (Fig. 131), 



BLEACHING LEATHER. 535 

which is provided with a pane of glass, closed, and the bellows 
worked slowly but uninterruptedly. 

The sulphur vapors carried along by the sulphurous acid 
evolved by the combustion of the sulphur are deposited upon 
the roofing tiles or condensed by the water in the vat W. 
The gas passes out through the narrow apertures of the pipe 
RR, and dissolves abundantly in the cold water. When the 
water has a strong odor of sulphurous acid and tastes sour, it 
is sufficiently impregnated with sulphurous acid. The bellows 
are then stopped and the cock in 5 is closed to prevent water 
from reaching the combustion apparatus in consequence of the 
sucking of fluid by the sulphurous acid contained in the cool- 
ing pipe. 

For bleaching purposes the sulphurous acid thus prepared 
is brought into small vats of suitable depth, and the wet sides 
of leather, suspended from poles, are immersed in it, so that 
they do not touch one another, and allowed to remain about 
two hours. They are then replaced by a fresh lot, which is 
allowed to remain for three hours, this being continued until 
the fluid shows but a very slight odor of sulphurous acid. 
The leather when taken from the bleaching fluid is immediately 
washed. 

BLEACHING WITH SODIUM PEROXIDE. 

Dissolve two pounds of Epsom salts in ten quarts of water, 
and add gradually to the solution ten ounces of sodium dioxide. 
Apply the fluid thus obtained to the leather to be bleached. 
To protect the leather from being injuriously affected by the 
bleaching agent, it is recommended to moisten the bleached 
portions with water slightly acidulated with acetic acid. 

BLEACHING WITH HYDROGEN PEROXIDE. 

Moisten the leather to be bleached with water, to which have 
been added a few drops of spirit of sal ammoniac, and then 
apply the hydrogen peroxide with a rag or a brush. Repeat 
these operations alternately until the leather is sufficiently 
bleached. 



536 THE MANUFACTURE OF LEATHER. 

BLEACHING WITH ALUMINIUM HYPOCHLORITE OR MAGNESIUM HYPOCHLORITE. 

These bleaching agents are formed by compounding chlor- 
ide of lime solution respectively with aluminium sulphate 
solution or with Epsom salt solution. A white precipitate of 
gypsum is formed, which in a short time deposits completely. 
The supernatant clear liquor is a very effective bleaching agent, 
and has the additional advantage of being cheap. It is applied 
to the leather, and after a few minutes wiped off by means of a 
wet rag or sponge. 

BLEACHING CHAMOIS LEATHER. 

Chamois leather cannot be bleached with sulphurous acid 
alone, and agents of a more vigorously oxidizing action have 
to be used in order to destroy the adhering coloring matter. 
For this purpose potassium permanganate may be recom- 
mended. Dissolve one part by weight of potassium perman- 
ganate in twenty parts by weight of water, spread the leather 
upon a table, apply the solution and rub it into the leather with 
a glass ball. During this manipulation the leather becomes 
constantly darker and finally brown, by reason of the potassium 
permanganate becoming decomposed and separating manganic 
oxide, which is of a brown color. 

The leather, after being thoroughly worked with the glass 
ball, is rinsed and immersed in solution of sulphurous acid^in 
water. The manganic oxide dissolves with ease, and the 
leather, after having been several times washed and finally 
dried, appears perfectly white. 

BLUING WHITE LEATHER. 

Kid leather, not pure white, can be made so by bluing. 
However, the operation has to be executed with great care, 
so as not to spoil the leather. Dissolve in one hundred 
quarts of water about three drachms of water-soluble aniline 
blue. Wash a skin in the solution and dry it. If, after dry- 
ing, the color is of a too yellow cast, add gradually very 
small quantities of the dye stuff until the desired tone is ob- 



BLEACHING LEATHER. 537 

tained. If, on the other hand, the leather is too blue, which 
is more frequently the case, add ten quarts of water to the bath 
and repeat this until the desired tone is obtained. 

By this simple treatment leather of a quite yellow shade may 
be obtained pure white, and water-blue leather may also be 
prepared ; in brief, the entire scale of colors between yellowish 
white and bluish white. It is, however, of importance always 
to ascertain the strength of the bath by an experiment with a 
single skin in order not to obtain leather too much blued. 

BLEACHING HEAVY LEATHER. 

The recipe here given is for bleaching bull's, stag's or russet 
harness leather : 

(i) For 25 sides, put six pounds of borax in five pails of 
water, so that the leather is entirely covered. Mill for 15 min- 
utes. (2) Dip each side in a strong solution of sulphuric acid 
(30 degrees), and immediately rinse each side in a vat of clear 
water. (3) Return the sides to the mill and put in 2^ or say 
3 pails of hot strong sumac. Pour in one quart of muriate of 
tin. Mill for 15 minutes. Take out. Slick off on grain side. 
Oil evenly over and hang up to sammy, suitable for setting. 
In setting, blend water with stuffing and stuff lightly over, just 
enough to lay the flesh smooth. The most important point is 
to remember to get the tannin out of the liquor before starting 
in the acids, by giving brisk scouring. For a table set for this 
bleached leather, cook one pound of starch in two gallons of 
water and one quart cod oil. If this mixture comes out a trifle 
heavy reduce with water. It will leave a nice white flesh on 
leather free from heavy greases. Care must be taken that none 
of this stuff gets on the grain side. Bleached leather ought to 
be dried in at least 36 hours ; the sooner the better, in order to 
get a nice uniform color. In bleaching light sides, say four to 
6 ounce stock, put 50 hides into the mill. 

The following recipe for bleaching leather appeared recently 
in the Ricettario del Conbiatoria : " An interesting product, re- 
cently introduced for the bleaching of silk and wool, has been 



538 THE MANUFACTURE OF LEATHER. 

successfully employed for the bleaching of leather. This agent 
is the dioxide of sodium. Sold in tin boxes, and having the 
appearance of powder, it must be kept far from wet and damp- 
ness, as it is liable to decompose quickly. When it is required 
for bleaching leather, the following is the process to be ob- 
served : Dissolve by heat two pounds of sulphate of magnesia 
in nine quarts of water, and when the solution gets cold, grad- 
ually add eleven ounces of dioxide of sodium. The leather 
required to be bleached is rubbed over with this solution until 
the desired white or clear color is obtained. If the leather to 
be treated is stout and heavy, the action of the solution may 
be assisted by first washing the leather with water slightly 
acidulated with acetic acid." 

IMPARTING A LIGHT COLOR TO LEATHER. 

Although the tanner will always strive to produce as light 
colored a leather as possible, since it commands a higher price, 
still circumstances may occur whereby it is essentially dark- 
ened. To correct this he will try to give it a light shade by 
artificial means, which however, if performed in an incorrect 
or careless manner, most generally enhances the outward ap- 
pearance of the leather at the cost of its interior quality. The 
toning down of dark leather will to a great extent remain a 
knack of the expert tanner, as long, at least, as there is a provo- 
cative cause ; in other words, bad tanning material on the one 
hand, and on the other as long as light colored leather is higher 
in price than dark, which is in other respects just as good. 
Since, however, the procedure of artificially toning down the 
color of the leather is fairly difficult, it may be well to enter 
into a few details how it is to be done, so as to cause the least 
injury to its intrinsic quality. 

A difference must at first be made between the simple ton- 
ing down and the direct bleaching. While in the latter pro- 
cedure the actual color of the leather is to disappear as nearly as 
possible, to be replaced by a more or less pure white, the aim 
of the former is to simply modify the dark hue and cause it to 



BLEACHING LEATHER. 539 

become paler; but it is not the purpose of the process to make 
the color disappear altogether, which has been recognized to 
be injurious, and perhaps requires the raising of the color 
again by artificial means. For this reason actual bleaching 
agents cannot be used for the simple toning down, or if em- 
ployed, they are to be applied with the greatest care, so as not 
to produce a leather white outside but dark within. The 
agents used for toning down are, as is well known, highly 
diluted acids, in which the leather is for a time steeped. Best 
liked because simplest in its application is highly diluted sul- 
phuric acid, or else acetic acid, while with lactic acid mixed 
with bran, there is danger that the surface of the leather be 
corroded. While it is undeniable that the toning of the color 
with these acids is injurious to the quality of the leather, the 
injury is in large part due to the circumstance that the process 
is incorrectly conducted. The principal fault lies in entering 
the more or less dry leather into the water very feebly acidu- 
lated with sulphuric acid. The immediate consequence is that 
the fluid penetrates into the innermost parts of the leather, in 
other words, saturates it, while as a toning agent it is simply 
required on the surface. Of course, another advantage is 
gained thereby, to wit, the leather is toned not only on its 
surface, but also in its interior, and the fact that it has been 
subjected to this treatment is not so readily detected. But 
this process is performed at the expense of the quality of the 
leather, because this is saturated into its core with sulphuric 
acid which, though in a highly diluted state, is not very easy 
to be gotten out again, consequently it can exert its damaging 
effects at leisure. It would therefore be a great improvement 
to immerse the leather first in clean soft water, with which it 
would become saturated, before being entered into the sul- 
phuric acid water. If the leather, already saturated with clean 
water, is entered into the acidulated water, little or else nothing 
of it enters into the interior, where it is really not wanted, and 
where it can simply become injurious, but it remains almost 
altogether on the surface, where it is wanted for toning the 



54-0 THE MANUFACTURE OF LEATHER. 

color. The importance of this modification will at once be 
apparent to every tanner, and it would also be of interest to 
the leather trade, because the interior quality of the leather 
would not suffer by applying the acidulated water on the sur- 
face. But here again the objection might be urged that the 
corrected color, in consequence of the non-penetration of the 
acid, modifies simply the surface, and the leather thus cor- 
rected can be readily distinguished. 

TO BLEACH SKINS WITH THE HAIR ON. 

The following methods may be employed with advantage 
for bleaching lamb or goat skins intended for rugs, lap- 
robes, etc. : A quick bleach is obtained by the use of liquid 
sulphurous acid, the skins having first been thoroughly freed 
from grease by washing in lukewarm soapsuds at a tempera- 
ture of about 82 F. Even more rapid and better results, 
especially in the bleaching of goatskins, are arrived at with 
Labarraque's solution (hypochlorite of soda) ; provided suffi- 
cient care is exercised to have the bleaching liquid just strong 
enough in chloride of sodium and the skins perfectly clean, a 
snow-white bleach can be obtained inside of two days by this 
method. The manner of preparing Labarraque's solution is 
as follows: Mix together 4^ pounds chloride of lime and 21 
quarts water, stirring frequently for some time. Leave the 
mixture standing until thoroughly settled, and then strain off 
the perfectly clear portion into a solution of io}4 quarts water 
in which have been dissolved 5 *4 pounds Glauber salts. An in- 
soluble precipitation of gypsum results, leaving the hypochlor- 
ite of soda in solution. The clear liquid, which should be quite 
free from lime, is next drawn off, and the skins immersed 
therein until thoroughly bleached, which takes about two days. 
After removing the skins from the bleaching liquor, rinse well 
and wash in weak soapsuds prepared of white oil-soap, in order 
to impart the necessary soft feel. 

Small lambskins can be treated satisfactorily by the method 
employed for bleaching hog bristles, namely, with permangan- 



BLEACHING LEATHER. 541 

ate of potash and bisulphite of soda. The previously cleansed 
skins are first immersed and worked for three-quarters of an 
hour in a bath prepared in the proportion of i T V pounds 
crude permanganate of potash to 130 gallons of water, heated 
to 95 F. At the expiration of the time mentioned they 
are removed and placed, without rinsing, in a second bath 
of 130 gallons of water to 7^ quarts bisulphide of 35 Be, and 
6S/& pounds hydrochloric acid of 20° Be, at a temperature of 
104 F., in which they are worked until perfectly bleached. 

As the question of cost of material and the actual expense of 
the bleaching process is of secondary importance only, the use 
of peroxide of hydrogen or peroxide of sodium is to be recom- 
mended. Experiments have proved that thoroughly clean 
lambskins can be bleached beautiful white in a few hours with 
the first-named chemical. The peroxide of hydrogen is diluted 
in 8 to 10 times its own weight of water, to which is added a 
little aqua ammonia, and the skins immersed until the desired 
result is attained. 



CHAPTER XLI. 



LACE LEATHER. 



Lace leathers are either tanned, tawed, or made from raw 
hides, and both these varieties as well as picker leathers, which 
are used for looms, and also for hamestrings, are generally pro- 
duced in the same tannery. But the variety of lace leather 
which we shall describe in this chapter is the lighter kind, 
which is manufactured usually from Calcutta hides, the heavier 
variety being made from light cow-hides. . 

When the dry Calcutta hides are used they are first placed 
to soak in a vat of water, and the time which . they remain is 
dependent upon the weather, one or two nights in warm 
weather and three or four nights in cold weather being the 
usual time. The water used for the soaks should be softened 
with borax, as has been previously described. 

They are next softened in the hide-mill, the time which they 
are worked depending upon the manner in which the hides 
have been cured. 

In order to cleanse them from dirt the hides are next placed 
in the wash-mill and worked for fifteen or twenty minutes with 
water softened with borax, which operation also removes the 
wrinkles. 

Upon being removed from the wash-mill, the hides are 
spread flat upon the floor and slit down the back and thus 
divided into sides. 

They are then placed upon trucks and carried to the lime- 
vats, where they are spread flat upon the floor alongside the 
vats and whitewashed, by passing over them a swab which has 
been dipped in a solution of lime. 

This coat of whitewash is applied to the hair side, and the 

(542) 



LACE LEATHER. 543 

sides are piled two hundred high, and in warm weather this 
pack remains over night, but in winter the sides are placed in 
the lime-vats the same day, in order to prevent the whitewash 
from chilling. In warm weather the sides remain in the limes 
about ten days, but in cold weather the period is longer. 

It is best to mix sodium sulphide with the lime, as the un- 
hairing is done more quickly and the gelatine of the hide is 
sound. 

When the hair is loosened, the sides are removed from the 
vats with tongs and immediately unhaired, after which they are 
placed in water in a vat having a revolving paddle wheel and 
washed, the England wheel and vat being the one commonly 
employed, and upon removal are worked on the beam to remove 
the lime. 

They are then fleshed and bated in C. T. bate (manufactured 
by Martin Dennis Chrome Tannage Co., Newark, N. J.). 

As a further preventive against lime the sides are placed in 
a large revolving wheel, called a "tub wheel," in which they 
are washed for about three-quarters of an hour, and upon re- 
moval from this wheel the sides are placed in the tanning 
liquors and remain until tanned. When this has been accom- 
plished the sides are exposed to the air to dry and next 
stretched, a machine for which purpose is shown in Figs. 132 
to 134; but the stretching is also performed by hand on the 
stretch- bench. 

As is well known, all hides vary considerably in thickness at 
different points, and when taken from the liquor-vats they are 
found to be soft, flabby, wrinkled and fulled. Owing, there- 
fore, to this condition of the hides, it is necessary, before they 
are dressed and finished for the market, that they be stretched 
throughout to remove the wrinkles and fulness, and also to re- 
duce those parts which are thicker than other portions, so that, 
as far as possible, the hides shall be uniform in thickness. 

Mechanical devices are capable of producing, in connection 
with hand manipulation, the desirable results of thoroughly 
stretching the hides, and rendering them of even thickness in 



544 THE MANUFACTURE OF LEATHER. 

all parts. These devices usually comprise, in the main, a fric- 
tion table or beam, over which the hides are dragged, a stretcher- 
bar of suitable form for stretching the hides transversely, and a 
slowly-revolving roller, to which -the edge of each hide is 
secured, and around which it is wound after being drawn over 
the table or beam and the stretcher- bar. After the sides have 
been well worked on the stretch-bench they are split evenly by 
the splitting machine. 

The sides are next stuffed with tallow and neat's-foot oil, the 
proportions of which change somewhat according to the tem- 
perature and season, less oil and more tallow being used in 
summer than in winter. 

If the tannage is alum or vitriol, stuff in a wheel with the 
stuffing 90 F. Curriers stuff leather when moist, but figure 
the material to every 100 pounds of dry leather. They 
get this weight by deducting one-third from the weight of the 
sammied leather to be stuffed. Therefore (reckoning on this 
basis), to 100 pounds of dry lace leather use 10 pounds tallow, 
10 pounds degras and 10 pounds cod oil, melted together 
and put in wheel at 90 F. Time of wheeling depends on 
tannage and speed of drum. It requires some time to get 
grease into alum leather. The wheel might have to be run one 
hour. In a larger wheel shorter time is necessary than in a 
smaller wheel. In an eight or ten foot drum three-quarters of 
an hour wheeling ought to suffice, and would keep the leather 
of a nice color. Grease tends to make tough leather. The 
heavier the grease the tougher the leather. If more oil is used, 
leather becomes soft and rather short-fibred. If it were possi- 
ble to stuff entirely by tallow the leather would be very tough. 

The sides are then hung upon sticks in tiers in the drying- 
room, which is commonly heated by exhaust steam from the 
engine. 

After being removed from the drying-room the sides are 
softened, the machine shown in Figs. 135 to 143 being now 
usually employed for this purpose in place of the old-fashioned 
pin-block. 



LACE LEATHER. 545 

The sides are next rolled out smoothly on a glassing machine, 
and then shaved on the flesh side and buffed with a currier's 
knife, in which latter operation the grain is removed in order to 
prevent the lacing from cracking; about seventy-five sides 
being a fair day's work for one man. They are next rubbed 
with a mixture of lard oil, tallow, and flour, and the sides of 
lace-leather are then finished by laying them upon a flat table 
and smoothing them out with a glass slicker. 

To obtain the golden yellow color so much desired in lace 
leather, an old experienced tanner recommends the addition of 
pulverized brimstone or sulphur to the tanning liquor. The 
sulphur acts as a tanning agent as well as a colorant. About 
2 oz. is the quantity of sulphur requisite to a side. For a 
darker shade, take 2 oz. japonica instead of sulphur, using it 
in same manner. 

junior's methods of manufacturing lace-leather. 

The following process for manufacturing lace-leather is used 
by Junior, of Belleville, 111. There is no patent on the process, 
but Mr. Junior claims one on the tanning compound, which 
patent has now expired. . 

The hides in this method go through the following pro- 
cesses : — 

First. Soak the hides in fresh water for twenty-four hours. 

Second. Soak the hides in freshly slaked lime-water as long 
as necessary to make the hair removable by scraping. 

Third. Put the unhaired hides into fresh lime-water once 
more for two days. 

Fourth. Scrape off all fleshy parts on the inside ; then soak 
the hides in fresh water to free them from all lime. 

Fifth. Then rub the hides with a " slick-stone," in order to 
smooth or burnish them and to squeeze out all impurities. 

Sixth. Soak the hides for about twelve hours in warm water, 
containing one pound of wheat bran and one-half pound of a 
ferment to every five gallons of water, until the hides cease to 
swell, and all lime is neutralized. 
35 



546 THE MANUFACTURE OF LEATHER. 

Seventh. Then squeeze them well with the scrape-iron. 

Eighth. Immerse the hides in the composition given below, 
in which they remain for from twelve to twenty-four hours until 
they are well saturated. 

This composition consists of the following ingredients com- 
bined in proportions stated : For every ten pounds of hide — 
pure water, five gallons; alum, one pound; sal-soda, four 
ounces; common salt, four ounces ; wheat bran (or other bran), 
four ounces. Of these ingredients the crystalline salts should 
be thoroughly dissolved and mingled by agitation with the bran. 
It is claimed that the application in tanning of this solution, in 
connection with the other treatment of the hides, has the effect 
of preserving the whole natural strength of the same, which is 
possible only in the absence of free acids. After the hides 
have become saturated, they are removed from the solution and 
hung up to dry. 

Ninth. Now work them well on the stretch-bench and split 
them evenly on the splitting-machine. 

Tenth. Rub into the hides a mixture of about three pounds 
of lard oil and one pound of tallow, and let dry well. 

Eleventh. Soak in rain-water containing bran, and in this 
wet state stretch the hides well on the stretch-bench. 

Twelfth. Now shave them as clean as possible on the flesh 
side, and especially carefully on the grain side, in order to re- 
move the whole grain, which removal produces the elasticity 
which prevents the liability to cracking. 

Thirteenth. Then finally, rub into the hides a mixture of one 
and one-half pounds of lard oil, one-half pound of tallow, and 
one-eighth pounds of fine flour for every ten pounds of hide 
(which process helps to produce smoothness and durability of 
the leather), let them dry, then stretch and smooth them well 
with a wooden stretcher, and now the hides are ready for use. 

QUICK TANNING PROCESS FOR LACE AND WHIP LEATHER. 

The method patented in 1875 by Bartenbach and Richter, of 
Detroit, Mich., is as follows : 



LACE LEATHER. 547 

For making lace and whip leather the hides are cleaned after 
soaking, the hair being removed. Then put them in the follow- 
ing solution, enough being used to fairly submerge them : To 
twenty-five gallons of warm water add two pounds of alum, 
fifteen pounds of salt, one pound of sulphuric acid, two pounds 
of wheat bran, two ounces of dissolved sulphur. The hides are 
left in this solution for twenty to twenty-five minutes, after 
which one ounce of vitriol, four pounds of salt, and two ounces 
of alum, dissolved in one-half gallon of water, are mixed with 
the solution, and the hides are left to remain in it twenty 
minutes longer. The hides are then taken out and well wrung, 
and hung up to dry in a dark, airy place. Those intended for 
whip leather, when dry, are moistened with a little water, and 
stretched upon a stretching-iron. Those intended for lacing- 
leather, after being well dried, are rubbed with a mixture of one 
pound of fish oil, one pound of tallow, four ounces of linseed 
oil, and two ounces of soap-soda in a gallon of hot water. 

loescher's method for manufacturing lace leather. 

In 1876 H. Loescher, of Chicago, 111., patented the following 
method for manufacturing lace leather, the object claimed being 
to produce lace leather of greater strength and tenacity than 
that produced by treating skins with lime and acids. 

The first step in this process is to remove the hair from the 
hide by fermentation by subjecting it to a decaying process for 
a few days. The next step is to dry the skin to a flinty hard- 
ness ; and the last step consists in subjecting the dried skin to a 
process of torsion and beating until thoroughly softened, when, 
it is claimed that it will have the toughness of rawhide, with 
the pliability of kid. 

coupe's stretching machine. 

The machine for stretching leather shown in Figs. 132 to 134 
is the invention of Wm. Coupe, of Attleborough, Mass., who is 
an extensive manufacturer of lace leather. 

Figure 132 represents a front elevation of Coupe's machine. 



548 



THE MANUFACTURE OF LEATHER. 



Fig. 133 shows the same in central vertical transverse section, 
and Fig. 134 represents the stretcher-bar in perspective. 

As particularly shown in Fig. 132, the machine consists of the 
following devices : A pair of standards as at A A 1 , in which is 
mounted a shaft, as at B, to which power is applied. Upon one 



Fig. 132. 




Fig 133. 




Fig. 134. 




end on this shaft is a pinion, as at C, arranged to mesh with a 
gear, as at D, loosely mounted on one end of a roller, as at E. 
The inner side of this gear, D, is provided with a clutch face 
or pin as at d, for engagement with a clutch as at F, splined to 
the roller E, and furnished with a slipping-handle as at G, so 
arranged as to be convenient of access to the operating 
attendant. The remaining parts of the machine consist of a 
narrow table or breast-beam as at H, which is mounted in 
mortises as at a, in the standards A A', and a stretcher-bar as 



LACE LEATHER. 549 

at K, likewise mounted-in mortises as at a', and having its two 
working faces doubly inclined as at k, k', Fig. 134. 

The operation of the machine is as follows : 

A hide is placed over the table or breast-beam, H, and one 
of its ends carried under the stretcher-bar, K, and secured to 
the roller, E, by the clamp, e, the other end hanging free in 
front of the machine, as shown in Fig. 133. The operator now 
connects the roller, E, to the continuously-revolving gear, D, 
by means of the handle, G, and clutch E, and the roller, E, 
slowly revolves, winding the hide around its surface, and draw- 
ing it over the friction table or beam, H, and around the 
stretching-bar, K. 

When any part of the hide, the thickness of which is to be re- 
duced, or the wrinkled or fulled-up portion smoothed out, passes 
over the table or beam, H, the operator who stands in front of 
the beam applies pressure by hand to the proper portions, 
thereby increasing the friction between the under surface of the 
hide and the surface of the bar, H, and causing the onward 
movement of such portions to be retarded. The portions thus 
pressed upon are more severely stretched than other parts of 
the hide, and by proper manipulation by the attendant its thick- 
ness is rendered uniform, and it passes to the stretching-bar, K, 
in a smooth condition, having been longitudinally stretched 
upon the beam, H. 

In passing over the bar, K, the hide is transversely stretched 
by the doubly-inclined sides, k, k', from which it passes onward 
to the roller, E, winding about the roller uniformly and smoothly. 
The machine is now stopped, the hide removed, another secured 
to the roller, E, and the operations above described are repeated. 

tidd's softening machine. 

Figs. 135 to 143 show the machine invented by J. Tidd, of 
Woburn, Mass., which is much used for softening lace leather. 

Fig. 135 is a side, and Fig. 136 an end elevation. Fig. 137 
shows the under side of the cross head G. Fig. 138 is a top 
view of the bed B. Fig. 139 is the under side of a grooved 



55o 



THE MANUFACTURE OF LEATHER. 



cross-head. Fig. 141 is the top side of a grooved bed. Fig. 
143 is a side view of a grooved cross-head, with a corrugated 
or serpentine rib /, instead of the pins C. Figs. 140 and 142 
are end views of Figs. 139 and 141. 




If 

< 1 



i 



Fig. 135. 



Fig. 136. 



' , WW 



4 



sip 



'4 ssssr i- J -~- 






Fig. 137. 




(0 


OfcOOOOOOO _\ 

0000000 ^y 




Fig. 138. 






6°o a o o o o°o 






Fig. 139. Fi 
*-' C r 


3.- I4O. 

^1 



The perforated bed B, is secured to the top of a supporting- 
beam K, in combination with a yielding cross-head G, and a 
series of pins c, projecting downward from the under side. 
Each perforation a in the bed B is directly under a correspond- 
ing pin in the cross-head. A shaft, H, is arranged in bearings at 
or near the centre, and near the bottom of the framework, and 
on each end of this shaft is a balance-wheel /, outside of the legs 
b, and on the same shaft inside of and near one leg is a pulley 



LACE LEATHER. 55 I 

A, to receive the belt which drives the machine. Projecting 
outward from each of the wheels /, are crank-pins or wrist-pins 
i, and the lower end of a pitman, k, connects with each pin i. 
The upper end of each pitman connects with the lower end of a 
vertical rod m, which passes freely through a hole in the beam 
K, and extends upward through the cross-head G. These rods 
m are screw-threaded from their upper ends downward to a 
little below the cross-head G, and the latter is connected with 
the rods m by nuts d beneath the cross-head, and by similar 
nuts e above. The nuts d are for raising or lowering the cross- 

Fig. 141. Fig. 142. 



Fig. 143. 



£ 



head to any desired point of adjustment, and the nuts e are to 
screw down or up, and increase, release,, or diminish the action 
of the springs g, which are arranged between the nuts e and 
the upper side of the cross-head G, so as to allow the latter to 
yield when the leather is placed on the perforated bed, beneath 
the cross-head and the pins c, the downward motion of which 
brings the lower ends of the pins into contact with the leather, 
pressing, forcing, or bending certain portions of the leather, and 
in succession other portions, across the edges of the perforation 
a, thereby limbering and softening the leather to the desired 
degree, or in proportion to the time the leather is moved about 
between the perforated bed and the pins and cross-head while 
in motion or action. 

Instead of perforated bed and the pins, there are sometimes 
used a grooved bed and a grooved cross-head, shown in Figs. 
139, 140, 141 and 142, and either straight or corrugated or 



552 THE MANUFACTURE OF LEATHER. 

serpentine horizontally, as in Fig. 141, but the perforated bed 
and the pins for softening most kinds of leather and hides are 
preferable, as they require less power, and have a tendency to 
enlarge the side or piece of leather or hide, by the peculiar 
operation of the pins and perforations drawing in every direc- 
tion ; whereas, in all previous modes of softening leather, such 
as pounding the leather with a wooden mallet when spread out 
on the tops of several pins promiscuously disposed, the leather 
was considerably contracted or reduced in size, and very im- 
perfectly and unequally softened. 

This machine is driven by a belt from some rotating pulley 
on to the pulley A, which rotates the shaft// and wheels or 
cranks /, through the medium of which, and the pitman k and 
rods m, the cross-head G and pins c are moved up and down 
about two hundred strokes per minute. The leather or the 
hide is moved or fed along over the bed B, while the pins c 
strike or press portions of the leather into the perforations, 
changing from one portion to another until the whole surface 
of the leather has been acted upon, and the entire side or piece 
of leather is well and perfectly softened. 



CHAPTER XLII. 

THE DYEING OF LEATHER. 

THE introduction of coal tar colors has given an almost un- 
limited range of shades and tones and methods of producing 
them. It is in this very large range that most of the colorist's 
troubles lie, making it an almost insurmountable difficulty to 
produce more than one lot of a uniform color. The currier 
must have a very large experience with the "crankisms" of the 
various dyestuffs and the conditions which govern their appli- 
cation in order to produce certain colors, and it is here that a 
knowledge of .chemistry combined with keen observation and 
care will stand him in good stead. The following hints may be 
of value to him in his efforts to obtain a uniformly colored lot: 
"The resulting color produced by brushing or dipping a piece 
of leather in a solution of aniline dye depends {a) on the 
strength of the solution ; (b) the time of duration of immersion 
or number of times the solution is brushed over it; (c) the 
temperature of the dye bath; (d) the nature of the mordant 
used before applying the dye; (e) nature of the "striker" or 
"topping agent" applied after the application of the dye; (f) 
the tanning process to which the leather has been subjected, 
whether hemlock, union, oak, sumac or tawed leather is being 
dyed ; {g) the temperature at which dyed leather is dressed, etc. 

As is well known, the so-called aniline colors, partly on ac- 
count of the beauty of their hues, with which they frequently 
unite a high degree of fastness, seem to be specially adapted 
for the purpose of leather dyeing, and are, almost all of them, 
greedily absorbed by, and fixed upon, the leather. For this 
reason a special mordant is barely ever required for preparing 
the leather for absorbing a color. It suffices generally to apply 

(553) 



554 THE MANUFACTURE OF LEATHER. 

the color directly upon the leather. It may be regarded as a 
general rule that an aqueous solution is much more readily 
absorbed, and the shades obtained are much clearer and 
brighter than when using an aniline soluble only in alcohol, for 
the very simple reason, because a finer-grade leather with deli- 
cate grain cannot well stand the treatment with strong alcoholic 
solutions. If a dye is to be used which is under no conditions 
soluble in water, the dyer must at least dilute the alcoholic 
solution of dyestuff with water to such a degree that the latter 
will just remain suspended in the liquor. It is self-evident, of 
course, that the process of dyeing can also with aniline dyes 
be performed in a manner similar to other dyes — by dipping 
into the fluid as well as by painting it on ; but in a few 
exceptional cases, it is better to effect the dyeing by painting 
on the color. Considering their capacity for being toned, 
the aniline dyes can be applied in almost all light shades 
of color. The greater part of the yellow, orange, brown and 
gray dyestuffs are applied by painting, though fuchsine and 
methyl violet are also applied in this manner. Should the one 
or the other aniline dye not take uniformly upon the leather, a 
mordant is to be used. Tanned leather which is rather dark, 
is best bleached first. This is done by drawing the leather 
several times through a strong, warm, sumac decoction, or else 
leaving it immersed in it for a few hours. A priming with pic- 
ric acid, also to be used in an aqueous solution, is to be recom- 
mended for several aniline colors. The dyestuff solutions must 
be prepared carefully in a suitable state of dilution, which is 
readily seen by testing upon a piece of glass or white paper. 

By the name of mordants the dyer designates a class of 
agents, the function of which is to prepare a material to be 
subjected to dyeing to receive, to "fix" the dyestuff upon the 
latter. According to their action upon a material, the gener- 
ally used mordants may be divided into three groups, to wit: 
i, acids; 2, bases; 3, salts. The bases hold a secondary place 
in leather dyeing. The most important are : Ammonia, caustic 
potash, and caustic lime. The important salts used in leather 



THE DYEING OF LEATHER. 55 5 

dyeing are: I, sulphate of iron; 2, sulphate of copper; 3, 
sulphate of zinc; 4, sulphate of alumina; 5, alum (a double 
combination of two sulphates); 6, nitrate of iron; 7, nitrate 
of lead; 8, chloride of ammonium; 9, chloride of iron; 10, 
chloride of tin ; 11, chlorate of tin; 12, chloride of sodium; 
13, acetate of iron; 14, acetate of alumina; 15, acetate of 
lead; 16, acetate of copper; 17, tartar; 18, carbonate of pot- 
ash; 19, carbonate of soda; 20, bichromate of potash; 21, 
chromate of lead; 22, potassium ferro-cyanide, etc. 

The most impoatant of the salts are the different soaps, 
formed by the action of an alkali upon a fat or an oil. A good 
hard soda soap is in general best for the purpose of leather 
dyeing, and the only point to be attended to is that it be white 
and not too strongly alkaline. The best sort is one prepared 
from olive oil, known in commerce as castile soap, and it is 
generally used for preparing the leather to absorb the dye- 
stuff. Before entering upon the actual process of coloring the 
leather, it is to be assorted according to its color, and destined 
to be dyed of a hue for which it is best suited. The hand- 
somest skins are used for light brown, lemon yellow, orange, 
violet, etc. Inferior ones are colored dark green, iron gray 
and black. It is best to prepare the colors for the occasion, 
and use them as soon as cold. Let the operator remember in 
this connection, that if he wishes to produce the possibly best 
effects, he must observe the greatest cleanliness in all the dif- 
ferent stages. The cloth or sieves through which the colors 
are strained, the vessels for them, the brushes, the tables, all 
must be kept scrupulously clean. There must be a brush for 
every color. 

Dark Brown. — Eight parts fustic, 1 part logwood, 2 parts 
Brazil wood, 1 part sanders, one- half part quercitron, are 
placed in a clean copper boiler, soft water is poured in so that 
it stands about two inches above the dyewood. The whole is 
boiled for about one hour, the decoction then strained through 
linen, and when cold used for dyeing. When the skin has 
been painted, it is rinsed with cold water while upon the table, 



556 THE MANUFACTURE OF LEATHER. 

the leather well stretched with a brass slicker, another coat of 
the dye is applied, again washed off with cold water, and the 
skin is rubbed until the water runs off clean. Colors that re- 
quire to be darkened, are washed with a solution of iron 
vitriol, consisting of 385 to 465 grains Salzburg vitriol * in 
three quarts of water. This solution is brushed evenly over 
the skin, and after having been absorbed somewhat, the latter 
is again washed with clean water, and set aside to dry. 

Light Brown. — The above-described color also serves for 
dyeing light brown, with this difference only, that a dilute pot- 
ash priming is given and the vitriol bath dispensed with. 

Olive Brown. — Two parts, by weight, of Hungarian fustic, 1 
part quercitron, and y£ part logwood are extracted by boiling, 
and the fluid is then applied upon a strong potash priming, a 
vitriol bath being subsequently given. 

Cutch Brown. — A decoction of 18 ozs. of cutch, with 42 
quarts of water and 2.1 1 ozs. of sulphate of copper, is applied 
upon the feebly-primed skin. 

Chestnut Brown. — The moistened leather is primed with a 
solution of 2^ lbs. of acetate of copper in 52 quarts water. It 
is then rubbed with the slicker, and a coating of yellow prus- 
siate of potash in slightly-acidulated water is applied. 

Chocolate Brown. — One and one-half parts Brazil wood are 
boiled in 45 parts water for two hours, after which a little pyro- 
lignite of iron is added, according to shade. 

Red. — A fine red of an admirable shade is produced by a 
coating with cochineal color, prepared of an optional strength 
by boiling cochineal in a linen bag in water, to which about 2 
per cent, aqua ammonia has been added. 

Alizarine Red (a feeble flesh color) is obtained by brushing 
over the leather a solution of alizarine or madder extract in 
dilute soda lye, after which rinse with soap water. 

Scarlet is produced by painting with Zaffer extract, espec- 
ially if the leather was previously primed with a feeble annatto 

*In chemistry called ferroso-cupric sulphate (mixed iron and copper vitriol). 



THE DYEING OF LEATHER. 557 

bottom. The Zaffer extract is diluted with water, in the pro- 
portion of about i part extract, 60 parts water, 1 part tartar. 

Ordinary Red. — An ordinary red is obtained by the decoc- 
tion of sanders wood upon a feeble priming of alum free from 
iron. 

Dark Green. — Four parts quercitron and 1 part logwood 
upon a strong priming with vitriol. 

Light Olive Green. — Give the leather a light bottom of Prus- 
sian blue, and then coat it with a decoction of 2^{ lbs. of fustic 
and y 2 lb. archil in 20 quarts of water. 

Picric Green. — The leather primed with Prussian blue is 
coated with a solution of picric acid in water. 

Lemon Yellow. — One part turmeric is digested in 4 parts 
alcohol at gentle heat for 24 hours, then diluted with water and 
applied upon a feeble potash bottom. 

Barberry Yellow. — Apply a coating with a decoction of 23^ 
lbs. of barberry root in 30 parts water, to which 7 ozs. alum 
free from iron are added. 

Orange. — A red priming color is produced with Brazil wood, 
a yellow with fustic; 75 parts Brazil wood and 25 parts fustic 
give a red orange ; 50 parts of the two an ordinary orange ; 
25 parts Brazil wood and 75 parts fustic a light orange. 

Chrome Yellow. — The dye is first applied with a solution of 
1 oz. of red chromate of potash in one pint of water, and is 
next fixed by 1 oz. of acetate of lead in one pint of water. 

In leather dyeing it is the custom to enter the goods at the 
maximum temperature, viz., about 11 2° F. ; the temperature is 
not maintained. The goods are turned over by hand in the 
dye-bath, a pair of skins at a time, care being taken that no 
single pair shall remain long at the bottom of the pile, from 
one dozen to three dozen skins, according to size, being dyed 
together in one bath. 

The manufacture of colored leather is a promising field. 
The tanner who knows how to get out novelties in this line 
may be sure of success. 

There are various methods of dyeing leather, such as the 



558 THE MANUFACTURE OF LEATHER. 

English method, or the one-tray process ; the Continental 
method, or two-tray process. 

The Continental method is approved of, on account of being 
able to prepare the second tray while the first is in use. The 
paddle method is not recommended, on account of the waste of 
dye and liquor, the same applying to the English tray method. 

Large paddles or reels are used in the paddle method, in 
which as many as twenty-five dozen skins or more are dyed in 
one bath, but a certain amount of coloring matter is wasted by 
being absorbed on the flesh side of the skins ; also the variety 
of shades obtained is greater, skin for skin, than when the older 
methods above mentioned are used. 

The one great advantage in paddle dyeing is the saving of 
labor, and it is therefore favored for common classes of goods. 

A large number of skins are also dyed by suspending them 
in a vat, out of which they can be occasionally raised for drip- 
ping by a block and tackle. 

In dyeing leather, the use of soft, bright, clear water permits 
the getting of good colors, particularly when bright shades are 
desired. 

Borax is the best agent for softening and brightening water. 

Wood dyes possess the advantage of being faster to light, 
and not so easily rubbed off, and consequently more durable 
than anilines. They are, however, dearer, and usually require 
expensive apparatus for their extraction. Aniline colors, on 
the other hand, are much more easily applied, are cheaper, 
more brilliant in color, but not fast to a strong light; many 
fading rapidly. 

It is possible to apply alizarine colors to chrome-tanned 
leather. In order to fix alizarine colors on leather, it is neces- 
sary to apply considerable heat ; for this reason they are not 
applicable to ordinary tanned goods. Chrome-tanned leather 
will, however, stand a high temperature without the slightest 
damage, and for this reason good results are got with alizarine 
dyes. 



THE DYEING OF LEATHER. 559 

INDIGO CARMINE. 

This coloring matter is the product of the action of strong 
sulphuric acid on indigo, and is of use to the leather manu- 
facturer, making white alums where perfectly white skins are 
required, giving the same result on this, kind of leather as ball 
or liquid bluing gives to white cotton cloth. 

YOUNG FUSTIC. 

This coloring matter consists of the wood of the sumac tree, 
and is the product of Bavaria and Southern France. 

Young fustic comes in sticks about six inches long and is cut 
into chips, the same as logwood or other dyewoods. 

This dyewood gives a greenish yellow shade and is used 
largely by manufacturers of glove leather. It is important that 
this young fustic should not be confounded with Cuba or so- 
called old fustic, which is altogether a different article. 

EXTRACT OF PEACH WOOD OR RED WOOD. 

This is an article which leather manufacturers, to a certain 
extent, have not given the attention it deserves. For a bottom 
to be used for dark colors, on mineral tanned, or in fact any 
tannage, it is a very valuable thing, giving a good base on which 
to put the aniline ; and at the same time it is a saving from the 
point that, with this base, the amount of aniline to be used is 
lessened. 

CREME OF LOGWOOD. 

One of the handiest and most reliable of the several articles 
on the market to replace the chip wood is that sold as creme 
of logwood, a concentrated, clarified liquor standing 51 Twd., 
extracted by a new process from the chips in such a way as not 
to start the tar or resinous matter from the wood, which is 
found in the general run of extracts, and so sure to make the 
dyeing liquor dull and muddy. Practical tests have proved 
this creme of logwood to be as cheap, money value, as the 
chips, and at all times insuring a uniform dye liquor ready for 
use at a moment's notice. 



560 THE MANUFACTURE OF LEATHER. 

This product is especially appreciated by consumers who are 
situated a long distance from the source of supply, on account 
of the great saving in freight, etc. 

No fixed rule can be laid down for the tanning and coloring 
of hides and skins. They must be treated according to their 
nature. 

In dyeing it is necessary to use the woods in conjunction with 
the anilines. 

In dyeing leathers with aniline dyes, sumac, bark, or gam- 
bier-tanned leathers take neutral dyes, but they can also be 
dyed with acid dyes. 

Alum-tanned leather takes acid dyes. 

Chrome tannage takes acid dyes, or must be treated with 
sumac in order to take neutral dyes, which is usually done. 

The chief object in shoe and furniture leather is fastness to 
light. The basic color of all dyes used for such leather is 
phosphine, which is fast to light, air, acids and alkalies. 

The leather to be dyed should be perfectly clean and free 
from grease. In order to accomplish this, skins are submitted 
to a process known as "clearing," which consists in passing 
them through a weak solution of potash and then through a 
weak sulphuric acid bath. As there are a great many colors 
which require sulphuric acid to "set" them on the leather, it is, 
of course, not necessary to wash the acid out until the dyeing 
is finished. On the other hand, some colors are very sensitive 
to the action of the acid, and hence it should be washed care- 
fully out before dyeing with them. 

Salable colored leathers must be uniform in color, and this 
can only be gotten by using pure reliable dyes. Good leather 
is often spoiled by bad dyes. 

WATERPROOF COLORS. 

These are prepared as follows, according to a process pat- 
ented in England by Dimitry: Two ingredients are made use 
of, one consisting of bichromate of potash, the other of a gelatin 
solution. These are mixed in suitable proportions and boiled, 



THE DYEING OF LEATHER. 56 1 

after which they are exposed to the sunlight. The mixture is 
then combined with a watery solution of aniline black, so as to 
form a thick pigment. It may also be employed with other 
aniline colors, which in this way become both acid and water- 
proof. 

MORDANTS. 

The few minerals which come into practical use in leather 
dyeing, are bichromate of potash, sulphate of iron, sulphate of 
alumina, sulphate of copper, and ferrocyanide of potassium. 

The first two mentioned are used for producing a dark or sad 
effect on leather dyed with the aniline colors, or for subduing 
the fiery tone of the brighter dyes. Sulphate of copper, or as 
it is commercially known, "blue vitriol," is also used for toning 
down a color. These three minerals are used either as mor- 
dants, or for toning the color after the aniline has been applied. 

Sulphate of alumina, or common alum, has exactly the op- 
posite effect, as it has a tendency to sharpen and bring out the 
brilliancy of most of the anilines. Ferrocyanide of potassium 
in conjunction with a solution of ferric sulphate, or copperas, 
produces a most beautiful mordant for any of the blue dyes. 

In using a mineral salt as a mordant, care should be taken 
that the salt in use is properly fixed in the fibre of the skin be- 
fore the aniline is applied. 

It is also advisable to remove any excess of mordanting so- 
lution which has not been absorbed by the skin, as the presence 
of the mineral salt in actual solution may have a deterrent effect 
on the penetrating qualities of the aniline. 

A mordant has served its purpose when it has become a com- 
ponent part of the skin, and the subsequent dyeing will result 
more satisfactorily if the superfluous mordanting liquor is re- 
moved from contact with the aniline. 

In dyeing with the aniline colors care should be taken to 
dissolve the dye thoroughly and in such a manner that no sed- 
iment shall remain in the vessel. 

The dye should never be applied to the skins until it has 
been well strained. 
36 



562 THE MANUFACTURE OF LEATHER. 

It is also well to repeat that uniformity of color can never 
be obtained where precautions are not taken in regard to 
cleanliness of vessels, etc., used in preparing the dye, as a ves- 
sel which has been used for some other purpose may contain 
traces of foreign matter sufficient to cause a chemical change 
in the aniline, which would prevent its going into the leather 
uniformly. 

Evenness of color on the skin can also be facilitated by di- 
viding the given amount of dye to a given weight of leather 
into 3 or 4 portions ; for instance, if 100 lbs. of leather required 
3 lbs. amaranth 3/Rto produce a desired shade, it would be 
well to divide the solution into three different vessels and apply 
the contents of the second vessel as soon as it is apparent that 
the skins have absorbed the dye from the first, and the third in 
sequence from the second, and so on. 

"tanners' preparation" for obtaining uniform colored leather. 

The continually increasing popularity of colored leather has 
engaged the attention of tanners more closely in recent years 
to perfecting the production of this commodity. Many 
methods in this connection have from time to time been 
placed on the market, but the vast majority have eventually 
proved to be failures, the chief difficulty encountered in the 
manufacture of salable colored leather apparently being the 
trouble experienced in successfully mordanting, clearing the 
grain, and removing all grease and animal matter from the 
leather prior to its reception of the coloring matter, it being a 
well-known fact that perfect abstraction of all grease and ani- 
mal matter is an absolute necessity, if uniformity and clearness 
of color are to be obtained. How to accomplish this desired 
result without injuring the leather is the problem which com- 
paratively few tanners have been able to solve with any degree 
of certainty. 

Gilbert Bros. & Co., Nos. 202 and 204 Purchase street, Bos- 
ton, have recently introduced an article of which they are the 
manufacturers, designated " Tanners' Preparation," which has 



THE DYEING OF LEATHER. 563 

been practically tested and is now being used by many of 
the most prominent manufacturers of colored leather, both in 
the United States and abroad, with highly gratifying success in 
removing the above-mentioned difficulties. The successful 
production of this " Tanners' Preparation " was only attained 
after months of experimenting, and by the possession of 
thoroughly practical knowledge on the subject of mordant treat- 
ment of leather by various compound salts and vegetable pro- 
ducts, acquired by years of study by the manufacturers. 

The process suggested by the manufacturers of this "Tanners' 
Preparation " is simply that it be used as a mordant for clear- 
ing after the skins are tanned, using about one part to fifty 
parts of water, regardless of the process of coloring or the 
colors used. Its principal advantages are that it removes all 
spots, grease and stains, thereby giving an evenness of shade 
and at the same time effecting a decided saving in the dyestuff. 

BLEEDING OR SMUTTING OFF OF COLORS. 

The so-called bleeding or smutting off of the colors upon 
goods dyed causes the greatest annoyances in the dyeing trade, 
and such effects must always be regarded as indicative of great 
faults in the application of coloring ingredients, or an injudic- 
ious choice of such substances for the respective fabrics treated. 
These troubles are frequently heard of in dyeing chrome black, 
and by the use of alizarine dyes. Such accidents were less fre- 
quently heard of when wood dyes were in general use, but in 
any case they can only be attributed to an imperfect handling 
of the dye stuffs. Some dyers are in the habit of substituting 
cheaper mordants and reviving agents for those recommended 
by the dye manufacturers, and even of reducing the necessary 
manipulations of the goods in order to save time. In such 
cases, this substitution might prove to have an effect incompat- 
ible with the coloring bodies, or the fibrous substances, and in 
some instances even cause decomposition of the coloring bodies, 
and prevent their fixing altogether. The mordants and dye 
stuffs can only upon perfectly clean surfaces be correctly devel- 



564 THE MANUFACTURE OF LEATHER. 

oped and fixed. If there are noxious foreign bodies present 
upon the fibrous substance, it can only cause a great waste 
of dye. 

THE PRACTICAL DYEING OF LEATHER WITH ANILINE COLORS. 

The accompanying samples were dyed in a practical way 
and taken from lots put through by the different firms men- 
tioned. 

They were done in a practical way and the formulas attached 
may be relied upon as being correct. The colors used are 
those that experience has taught us as being particularly 
adapted for leather, and from which shades can be produced at 
a reasonable cost. In dissolving aniline colors it is well to 
have the water heated to about 180 F. ; the color added and 
allowed to go into solution ; then bring to boil for several 
minutes. 

Sample No. I. 
RUSSIA CALF — COMBINATION TANNAGE. 
Tanned and colored by Bernard Freidman & Co., Danvers, Mass. 
For 30 feet stock 3 skins, used 3 oz. Leather brown F. Run in pin wheel ^ 
hour. Color furnished by F. E. Atteaux & Co., Boston, Mass. 



Sample No. II. 

RUSSIA CALF — COMBINATION TANNAGE. 

Tanned and colored by E. A. Muller, North Cambridge, Mass. 
Ox-blood shade. 5 doz. small calf skins. Run 10 minutes in wheel with 50 gal- 
lons water to dampen out and soften leather; temperature 90 F.; then handle as 
follows : 

1% lbs. Tartar Emetic. Run 15 minutes. 

2 lbs. Amaranth, 3-R, added in four separate parts. First part run 10 minutes and 
succeeding ones 15 minutes each. 

Then add 12 ozs. Amaranth, i-R. 1 „ «, , 
" " 4 " Chocolate brown O. J 
" " 3 lbs. Palermo fig soap. 
" " 5 lbs. pure egg yolk. 
" " 5 ozs. bichromate potash. 
Add in above order. 
Dye furnished by F. E. Atteaux & Co., Boston, Mass. 



II. 



III. 




IV. 




V. 



VI. 




VII. 




X. 





VIII. 



XI. 





IX. 




XII. 



Page 564. 



THE DYEING OF LEATHER. 565 

Sample No. III. 
CLOVE SHEEP LEATHER — ATTEAUX O. B. MINERAL TAN. 
Natural color of the leather as it comes from the tan. 
Tanned by F. C. Rose, Gloversville, N. Y. 



Sample No. IV. 
SHEEP SKIN — SUMAC TANNAGE. 
Tanned and colored by A. C. Lawrence & Co., Peabody, Mass. 
For large skins 1 oz. leather blue No. 1 to dozen skins. 
Color furnished by F. E. Atteaux & Co., Boston, Mass. 



Sample No. V. 
TANNAGE — ATTEAUX O. B. MINERAL TAN. 
For I dozen pickle sheep, 6 oz. fulling red for leather. Run % hour. 
Tanned and colored by F. C. Rose, Gloversville, N. Y. 
Dye furnished by F. E. Atteaux & Co., Boston, Mass. 



Sample No. VI. 
TANNAGE — ATTEAUX O. B. MINERAL TAN. 

For I doz. Goat Skins (Russian). 

Light bottom pure fustic extracts 51 , run 10 minutes. 

3 ozs. dark green M., 1% ozs. amaranth i-R., run 15 minutes. 

Tanned and colored by Weber Leather Co., Lynn, Mass. 

Dye furnished by F. E. Atteaux & Co., Boston, Mass. 



Sample No. VII. 
INDIA TANNED GOAT. 
Colored and finished by Donohue Bros., Lynn, Mass. 

For 1 doz. skins, cleared in borax and sal soda water, dyed with 4 ozs. nut brown 
O," with a very light chrome on top. 
Color furnished by F. E. Atteaux & Co., Boston, Mass. 



> 



Sample No. VIII. 
SHEEP 
Tanned with the Atteaux O. B. Mineral Tan. 
Tanned and colored by F. C. Rose, Gloversville, N. Y. 

Colored as follows : 14 doz. skins — 2% lbs. yellow II., 2 lbs. ext. fustic solid. 
Fat liquored as follows : A mixture 40 lbs. light English sod oil, 20 lbs. Palermo 
fig soap, 50 galls, water. 

Used % pail of above mixture to each dozen skins. 
Dye furnished by F. E. Atteaux & Co., Boston, Mass. 



566 THE MANUFACTURE OF LEATHER. 

Sample No. IX. 

DARK GREEN INDIA TANNED GOAT SKIN. 

Colored and finished by P. D. Egan, Salem, Mass. 

For I doz. skins: I oz. Bichromate Potash, 10 minutes; 2 ozs. Direct Green " B," 
10 minutes; I oz. Bichromate Potash, 10 minutes; % oz - Copperas, 10 minutes. 
Dye furnished by F. E. Atteaux & Co., Boston, Mass. 



Sample No. X. 

PICKLE SHEEP SKIN TANNAGE — TWO BATH CHROME. 

Dark ox blood. 

For I dozen sheepskins. Put skins in 20 gallons water at 1 io° F. Dissolve 1 lb • 
fustic extract and 2 lbs. peachwood extract in boiling water. Stir while in water and 
add above. Run ^ hour. Then dissolve 6 ozs. amaranth 3-R — % oz. malachite 
green in 1 gallon water. Then add another gallon boiling water and 1 oz. bichromate 
of potash. 



Sample A r o. XI. 

FOR I DOZEN SHEEP SKINS — HEMLOCK TANNAGE. 

Tanned and colored by Geo. E. Hayes, Peabody, Mass. 

4 ounces fulling red. Run 20 minutes. Then add y^ ounce bichromate potash 
and run 10 minutes longer. 

Color furnished by F. E. Atteaux & Co., Boston, Mass. 



Sample No. XII. 
GOAT SKIN — ATTEAUX, O. B. MINERAL TAN. 

Tanned and colored by Weber Leather Co., Lynn, Mass. 

For 500 lbs. leather. 

5 lbs. pure extract fustic, 51 , 7 minutes. 

2 lbs. haematoxylin powder, 7 minutes. 

1 lb. 6 oz. anilin yellow, 7 minutes. 

13 oz. chrome brown, B, 7 minutes. 

4 oz. golden orange, 7 minutes. 

12 oz. bichromate potash, 7 minutes. 

Before adding each of above they were dissolved in 3 buckets water. 

Fat liquor, ^ P an pure egg yolk. 

Dye furnished by F. E. Atteaux & Co., Boston, Mass. 



The following list of aniline and alizarine colors that work to 
advantage on leather and are being used in a general way 
among leather manufacturers. They are furnished by F. E. 
Atteaux & Co., Boston, Mass. : 



THE DYEING OF LEATHER. 



567 



Amaranth 1 / R. 
" 2 / R. 

" 3/R- 
Leather Red i/B. 
« 3/B. 
Safranine. 
Eosine. 
Fast Red. 
Archil Substitute. 
Grenat. 
Russia Red. 
Imperial Red. 
Fuchsine F. B. 
Maroon for Leather. 
Bordeaux Extra. 
Blood Red. 
Olive 11. 
Norwood Olive. 
Phloxine. 

Violets 1 / R to 5 / R. 
Violets i/Bto 6/B. 
Acid Violet. 
Malachite Green. 
Fast Green. 
Brilliant Green. 
China Green. 
Fmerald Green. 
Victoria Green. 
Dark Green S. 
Pure Blue. 
Alizarine Brown O. 
Red W. B. 

" Red B. 
Diamond Brown M. 
Sienna Brown R. 



Sienna Brown Y. 
Middleton Brown. 
Leather Brown, Extra. 
Bismarck Brown Y S. 
Bismarck Brown R. S. 
Mokka Brown. 
Cutch Brown. 
Dominion Brown. 
Terra Cotta Brown. 
Mahogany Brown. 
Acid Brown R. 
Acid Brown B. 
Acid Brown G. 
Nankin Brown Lumps. 
" Brown B S R. 
Leather Brown B S R. 
Chocolate Brown O. 
Chocolate Brown 270. 
Brown 361 for Leather. 
Olive Brown K. 
Seal Brown. 
Nankin Brown R. 
Leather Brown No. 200. 
Methylene Blue. 
Guernsey Blue. 
Fast Blue. 
Gentianine Blue. 
Nicholson Blue. 
Soluble Blue. 
Alizarine Brown Y. 
" Orange. 
Violet. 
Phosphine. 
Yellow 849. 
Flesh Yellow. 



Sun Yellow. 
Azo Yellow. 
Leather Yellow A. 
Fast Yellow F. 
Acid Yellow F. 
Mimosa Yellow. 
Chrysodine. 
Lemon Yellow. 
Boston Yellow. 
Naphthol Yellow. 
Leather Yellow No. 15. 
Orange I. 

" II. 

" IV. 

" D. 
Chrome Orange. 
Vici Drab. 
Bluish Grey. 
Silver Grey. 
Ink Black. 
Acid Black L. 
Pure Black. 
G G S Black. 
Nigrosine P. 
Nigrosine Extra. 
Nigrosine B. 
Indigotine. 
Blue No. 444. 
Alizarine Yellow. 
" Blue. 
" Mordant. 
Curcumine. 
Citronine. 
Vesuvine R. 



FORMULA FOR OBTAINING THE CORRECT OX-BLOOD SHADE ON COMBINATION 

TAN OR STRAIGHT GAMBIER TANNED CALF SKINS, FURNISHED BY 

F. E. ATTEAUX & CO., BOSTON, MASS. 

I dozen calf skins averaging 10 feet each. 

Take 10 lbs. hypernic chips; boil thoroughly and strain 
through cheese cloth or bagging. Put skins in wheel with 
sufficient warm water (temperature 8o° F.) to float them. 
Add the hypernic solution by degrees while the wheel is in 



568 THE MANUFACTURE OF LEATHER. 

motion ; run wheel x / 2 hour. Take 7 oz. amaranth 3-R, put it 
in a clean, dry pail and pour slowly over it a gallon of boiling 
water ; keep stirring all the time. Then hold the pail under a 
steam pipe and boil thoroughly for 10 minutes; strain through 
cheese cloth and cool down to no° F. by adding cold water. 
Divide this into 3 parts and apply to skins at intervals of 5 
minutes, and wheel for 1 5 minutes after the last portion of the 
dye went in. 

Take the skins out and dip them in a barrel of clean, warm 
water. Run off the waste dye liquor and wash the wheel out. 

Put clean, warm water in wheel (enough to cover the skins), 
put the skins back in wheel, then dissolve 3 oz. bichromate 
potash in 2 gallons of hot water and apply to skins while the 
wheel is in motion. Run wheel 15 minutes. 

The color should not fade if you take proper care of the 
temperature of your liquors. Do not let it get colder than 90 
F., and do not go higher than no° F., or the skins will draw. 

It is important that you boil the aniline thoroughly. You 
will lessen the liability to fade by fat-liquoring your skins im- 
mediately after coloring. 

Strike them out first to remove surplus water; then fat 
liquor. 

Dry slowly in an even temperature. 

Patent phosphine G. G., as shown in the leather sample No. 
13, for which we are indebted to A. Klipstein & Co., is one of 
the most valuable materials for makers of colored leathers, 
combining, as it does, most unusual fastness to light and dura- 
bility of shade with moderate cost. This is one of the newest 
and best of the full line of colors carried by this firm, whose 
enviable reputation gained by an intimate acquaintance with 
the leather manufacturers during the past quarter of a century 
is a guarantee of the reliability of their information in respect 
to these colors. 

Their head office is in New York, with branches at Philadel- 
phia, Boston, Chicago, Providence, Cincinnati and Hamilton, 
Ont. 













XIII. 




XIV. 











Page 568. 



THE DYEING OP LEATHER. 569 

Sample No. 14 is a specimen of quebracho-tanned leather 
which is also furnished by A. Klipstein & Co., New York. 

They are the largest importers of quebracho extract in this 
country, and carry a large stock at their main warehouse in 
New York and at their various branches. 

The advantages of using quebracho may be summed up as 
follows : 

1. It makes the most pliable leather because 

2. It tans all the way through the hide, consequently 

3. It increases the weight of leather obtainer. 

4. It tans more rapidly, and 

5. It tans more denser solutions than any other tanning 
agent. 

6. It is the cheapest tannage known. 

CALF LEATHER DYEING. 

Calf is among leathers what silk is among textile fibres, for it 
is readily dyed of all shades. There are, however, certain 
difficulties which many manufacturers never overcome, and im- 
portant among these are those which arise from improper pre- 
paration of the leather. In small works the preliminary 
softening is effected by a short soaking in sufficient luke-warm 
water to cover the leather, followed by an hour's pounding 
with oak stamps. Water at 104 F. is then run into the vat, and 
the goods are thoroughly handled for some time ; the turbid 
water is drained off, and the stamping and handling repeated 
until the right degree of slipperiness has been attained. 
Tumblers replace the stamps in larger works. After the soften- 
ing process the leathers are made up into pairs, one leather 
being stretched grain downwards on a glass or zinc table, and 
another stretched on the top of this one with the grain up- 
wards ; this affords an opportunity for striking out certain 
blemishes, and is also conducive to economy of dyestuffs, 
since the flesh sides are not exposed in the dye-bath. 

The water for the dye-bath should be acidulated with acetic 
acid to avoid the hardening effect of calcareous matters on the 



570 THE MANUFACTURE OF LEATHER. 

leather. For light shades, alum or bichromate of potash are the 
mordants ; for medium tones, a purer acetate of iron is used ; 
whilst pyrolignite of iron (about 15 B.), nitrate of iron (30 
B.), or sulphate of iron (30 B.), serve for the darker shades. 
Alum is but little used. Bichromate of potash is applied to the 
extent of 10-20 grammes (154.32 to 308.64 grains) per pair of 
leathers, the whole being generally added at once. The leather 
is well handled in the bath for 10 minutes, and transferred to a 
fresh bath, to which a small portion of the dyestuff has been 
added ; into a second fresh bath the remainder of the dyestuft 
is introduced, and the dyeing is completed therein. If a 
smaller proportion of bichromate is being used, the dyeing can 
be completed in the first bath. When iron mordants are used, 
acetic acid must be present in the mordant bath, and it is ad- 
vantageous to use the feeblest iron salts for grounding. A 
dilute iron mordant (the purer acetate at 2° B., or pyro- 
lignite at about io° B.) saddens gradually, whilst a stronger 
liquor is very active and " goes quickly on," so that uneven 
dyeing easily results. Cold-washing after the iron mordant is 
to be avoided, since the leather is thereby hardened. The 
foregoing mordants are for basic dyestuffs, acid dyestuffs not 
being amenable to such treatment. 

The following list of leather dyes is given : 



Auramine. Quinoline yellow. 

Phosphine N. Naphthol yellow. 

Philadelphia yellow. Curcurmen. 

Leather yellow. India yellow. 

Aniline yellow. Azo acid yellow. 

Phosphine P. H. Orange I I. 

New Phosphine. Mandarin G. extra. 

Phosphine superfine. Ponceau B O. extra. 

Thioflavine T. Ponceau 3 R B. 

Xanthine. Scarlet for leather. 

Canelle. Ponceau B extra. 

Leather red. Pure blue. 

Grenadine. China blue. 

Camelia B. Bavarian blue. 



THE DYEING OF LEATHER. 571 

Russia-leather red. Fast blue for leather. 

Bismarck brown. Acid green. 

Manchester brown P S. Guinea green. 

Vesuvine. Fast brown O. 

Cachou brown D. Fast brown 3 B. 

Leather brown A and B. Eosin. 

Malachite green. Erythrosin. 

Diamond green. Phloxin. 

Methylene blue. Rhodamine. 

Methylene dark blue B R. Nigrosin. 
Coal black. 
Leather black. 
Leather black 4252. 

THE DYEING OF LEATHER FOR SHOES. 

A largely increased demand for brown shoe leather has been 
evident for the last few years. Leather for this purpose is 
manufactured principally from calf skin for the better article, 
and from sheep skin for the inferior. Sheep skins already 
tanned are largely imported from Australia and New Zealand 
into England. The tanning agent in this case is the bark of the 
various species of acacia, natives of Australia, which contain 
the deep red mimotannic acid, and consequently the tannage is 
of a reddish tint. These skins are capable of being dyed really 
beautiful colors, and when carefully dyed and finished the 
better qualities make a fine article at a comparatively low price, 
but, of course, with nothing like the resistance to wear of a calf 
skin. The process for preparing tanned calf skins for dyeing is 
as follows : During the tanning process a large quantity of 
ellagic acid is almost invariably precipitated, and intimately 
mixed with the fibres of the skin. This is technically known 
as bloom, and must be removed before dyeing, or very poor 
uneven shades will result. 

Previous to this operation the goods are shaved down to the 
required substance. They should then be tumbled with warm 
water in a revolving drum to break and soften them, and this 
operation also removes a portion of the bloom. The skins are 
next taken out one at a time and placed on a marble or glass 
slab, each skin being knocked out perfectly flat and level so 



572 THE MANUFACTURE OF LEATHER. 

that it attaches itself, as it were, to the slab This is done by 
the men with what is known as a brass slicker. With this tool 
the grain of the skin is pushed out smooth until it presents an 
even surface. The grain of the skin is now scoured with a 
sort of brush made by tying up a piece of brass into a suitable 
shape ; by this process and a repetition of the slicking out the 
bloom is removed from the skin. The skins are next worked 
in a warm and very weak solution of soda crystals to remove 
surface grease. They are then taken to a bath of sulphuric acid 
of about f per cent, strength and worked about in this for ten 
minutes, after which they are knocked about in running fresh 
water until they no longer taste of acid, or if to be dyed with acid 
coloring matters, only slightly so. After draining on a horse 
or trestle for some time the skins are slicked out on the grain 
side until they present an even surface ; they are then placed 
flesh side together in pairs ready for the dye-bath. 

Dyeing Calf Skins for Shoe Work. — It will readily be seen 
from the great difference in weight of similar-sized skins and by 
the fact that only the grain side of the skin must necessarily be 
dyed, that it is impossible to calculate percentages of coloring 
matter simply to weight of skins. One must perforce use 
different percentages for different classes and sizes of skins, also 
for different tannages ; the correct proportions for different 
tannages, etc., being only learned by experience. The acid 
coloring matters are so easily applied to leather and the results 
are so satisfactory, that they are to a large extent replacing 
other classes of coloring matters. 

With the following three colors almost any shade of brown 
which will be required for shoe purposes may be obtained, 
viz.: Azo flavine RS, fast brown, blue black (induline). 

For instance, by combination of eight parts azo flavine and 
half part fast brown, the light Russian brown shade, which is so 
much worn, may be produced. 

Four parts azo flavine, one part fast brown and half part blue 
black will produce a medium shade of brown. 

Four parts azo flavine and two parts fast brown produce a 
red brown. 



THE DYEING OF LEATHER. 573 

To produce a chocolate or dark brown, one part blue black 
and one part fast brown are applied to the skins, four parts azo 
flavine and one part fast brown being afterwards added to the 
same bath. 

The varieties of colored leather used for shoes are becoming 
more marked each year. From solemn black to sober brown 
was the first step, and then the browns grew lighter and lighter 
until they reached the custard tint. After the browns came the 
reds and the ox- blood tints were the thing, and now we are drift- 
ing into blue and green tints foi ladies' shoes. These fancy 
colors all make money while novel, but they are liable to go 
out of fashion any day. However the bold spirits who are able 
to furnish promptly whatever colored leather is wanted will 
make the money if agile enough to return to beaten paths at 
the right time. 

DIRECTIONS FOR OBTAINING CORRECT OX-BLOOD SHADE ON ONE DOZEN 
CHROME TANNED CALFSKINS. 

The following instructions are given by F. E. Atteaux & Co., 
the well-known dye-stuff house of Boston, Mass. : 

Dissolve i lb. extract of fustic and 2 lbs. extract of peach- 
wood in boiling water. Put skins in the wheel with 30 gal- 
lons of water, temperature 110 F. ; stir while in motion and 
add above decoction by degrees, either through open door of 
wheel or through funnel attached to journal bearings of wheel. 
Run for half hour. Then dissolve in bucket 12 ozs. amaranth 
3/R with 1 gallon boiling water and add 8 ozs. white glycerine ; 
stir constantly while adding boiling water and glycerine. Then 
add another gallon of boiling water and hold pail under steam 
pipe, stirring all the time until the aniline is thoroughly dis- 
solved. 

•* Have another bucket ready, over the top of which is spread 
a piece of cheese-cloth or fine bagging, and allow this mixture 
to run through the screen. Then cool off with cold water to 
no° F. and apply same to skins in wheel in the same manner 
-as the preparation first mentioned, doing this while the wheel 



574 THE MANUFACTURE OF LEATHER. 

is in motion. Run them half hour, then take out skins and 
dip separately in barrel of clean water. Run off waste dye- 
liquor and wash wheel out. Dissolve 2 ozs. bichromate of 
potash in water and add to skins as the other liquors were 
added. Run wheel for fifteen minutes, then take skins out and 
lay away grain to grain for half hour before striking out. In 
setting grain use brass slickers. 

Note. — Do not at any time during the operation allow the 
temperature of the water in the wheel to fall below ioo° F. 

Do not stop the wheel under any circumstances until the dye 
has been in for at least ten minutes. 

Be sure all utensils are perfectly clean. 

Shade of color desired is a matter of judgment. A greater 
depth of color can be obtained by increasing the strength of 
the mordant or the first liquor as described above. 

For a light shade of ox-blood, increase the proportion of 
fustic extract and use less of the peachwood. 

If sumac extract be used for a mordant in place of the one 
we have mentioned above, use I lb. of the extract to I dozen 
calfskins. 

All dye, etc., should be thoroughly boiled and should be 
cooled with water before being put in the wheel. 

It is of the greatest importance to keep the skins in motion 
while adding any of the dyeing material. 

METHODS OF DYEING LEATHER USED IN GERMANY — PREPARING THE DYE 

BATH. 

When a leather has been mordanted with a mordant of de- 
termined concentration, a certain quantity of mordant is present 
upon a definite surface of the leather, for instance upon a 
square inch, and with the proper use of the mordant this pro- 
portion is the same upon the entire surface of the leather, i. e., 
each surface of one square inch contains the same amount of 
mordant. 

However, a determined quantity of the mordant will also fix 
a definite quantity of coloring matter and with a uniform distri- 



THE DYEING OF LEATHER. 575 

bution of the mordant over the entire surface of the leather the 
intensity of the color will be alike everywhere. 

Hence it will be seen that the depth of a certain color is de- 
pendent on the quantity of mordant present upon a definite 
surface; i. e., if a mordant of determined concentration is ap- 
plied to the surface, the result of dyeing will be a certain 
definite shade of the respective colors. With a mordant of 
greater concentration the result will be a darker shade of the 
same color, while with a more dilute mordant a lighter shade 
of the same color will be obtained. 

When working with a substantive coloring matter, i. e., a 
coloring matter which combines with the fibre of the leather 
without the necessity of using a mordant, a saturated solution 
will give the darkest tone the respective coloring matter is 
capable of producing, and, on the other hand, the more the 
solutions are diluted the lighter the shades will be. 

It is well known that in dyeing leather, and especially in 
dyeing kid, such advancement has been made that with one 
and the same color, for instance, pigeon gray or fawn, such 
numerous modifications may be produced that by laying the 
dyed leathers alongside one another, a complete scale of 
colors, from the most delicate gray or light brown to the 
darkest gray or brown, may be established. 

Now in order not to work at hap- hazard and not to make 
the hitting of a certain desired color dependent on the skill of 
the workman, it is of importance to find means by which the 
shades to be produced may once for all be fixed. 

If, for instance, a color is to be produced which is to be 
formed by fixing the coloring matter of a wood upon the 
leather by means of tin oxide or alumina, a definite tone of 
color may be obtained by working according to one or the 
other of the following processes : 

A mordant of tin-salt containing an accurately determined 
quantity of tin-salt is prepared as follows : Dissolve an accur- 
ately weighed quantity of the salt in water, and apportion this 
quantity to a corresponding number of skins. Instead of 



576 THE MANUFACTURE OF LEATHER. 

directly weighing, the content of tin-salt in the mordant might 
also be determined by means of an areometer. 

Now, theoretically, with the use of a solution containing an 
accurately determined quantity of tin-salt a definite tone of 
color should be formed, but in the practice it is, for several 
reasons, scarcely possible to obtain satisfactory results by this 
method. 

On the one hand, it is not so easy as it would appear at the 
first glance, always to weigh with the utmost accuracy the 
same quantities of a body, or to determine with positive exact- 
ness the density of a solution, as is absolutely necessary in this 
case, while on the other, the skins to be treated are not all of 
the same size, and even if worked alike their power of absorb- 
ing fluids may vary. Furthermore it must be taken into con- 
sideration that tawed leather already contains a body, alumina, 
which possesses the property of fixing coloring matters, and 
that the animal skin, even in the form of leather, is capable of 
separating certain quantities of coloring matters, though not 
substantive ones, which it retains so tenaciously that they 
cannot be removed even by long-continued washing. Hence 
with the use of mordants, the content of tin-salt of which has 
been accurately determined, quite definite tones cannot be pro- 
duced with absolute certainty, there being many difficulties in 
the way of the practical execution of this method, though theo- 
retically it is correct. 

The other method consists in using solutions of coloring 
matters of an exactly determined concentration. In this 
manner it is certainly possible to obtain satisfactory results, the 
process having besides the advantage of being suitable for 
substantive colors as well as for colors which can only be fixed 
by a mordant. This process is based upon the fact that a fluid 
is capable of dissolving only a certain, exactly determined, 
quantity of a body. 

By boiling, for instance, Brazil wood in water, a certain 
quantity of the coloring matter is dissolved, but afterwards no 
more will pass into solution even if boiling be continued for 



THE DYEING OF LEATHER. 577 

any length of time. Such a solution is saturated, and in this 
case is called a hot saturated solution. 

By cooling a hot-saturated solution to the ordinary tempera- 
ture, a certain quantity of the body held in solution re-separates, 
and we have then what is called a cold-saturated solution. The 
ordinary temperature of living rooms is about 6o° to 65 ° F., 
and it may be assumed that within these temperatures a cold- 
saturated solution of coloring matter in water, which has been 
prepared by boiling and then allowed to cool, always contains 
tie same quantities of coloring matter. 

Hence, by preparing a decoction of a coloring matter and 
allowing it to cool to the ordinary temperature, a dye-bath is 
obtained which always contains the same quantities of coloring 
matter. By dyeing mordanted leather in this dye-bath, which 
may be used cold or warm, the same shade of color is always 
obtained. 

Now, it is not difficult to prepare, with the assistance of such 
cold saturated dye-bath, fluids which produce determined 
lighter shades of color, it being only necessary for this pur- 
pose to dilute the bath according to a definite system. 

Dilution is best effected by preparing the dye-bath according 
to 100 parts. By adding to 95 quarts dye-bath 5 quarts water, 
a bath is obtained which contains -£$ less coloring matter than 
the original cold saturated solution ; by adding to 90 quarts 
dye-bath 10 quarts water, a bath is obtained which contains -£$ 
less coloring matter, and so on. Hence, in this manner, by 
mixing 95, 90, 85, 80, etc., quarts of dye-bath with 5, 10, 15, 
20, etc., quarts of water, baths are obtained, the amount of 
coloring matter of which decreases according to a certain pro- 
portion, and in dyeing these fluids will yield definite tones of 
color. 

By dyeing with such fluids a sample scale of leather, it can 
be immediately ascertained by comparison in what proportion 
the dye-bath has to be diluted for the production of a certain 
shade according to sample. By the use of such a systemati- 
cally arranged color-scale beautiful results are readily obtained 
37 



578 THE MANUFACTURE OF LEATHER. 

when coloring matters by themselves are used for dyeing a 
leather, the matter being, however, more difficult with blended 
colors which are not produced by one coloring matter alone. 
However, even in this case it will not be difficult for the ex- 
perienced workman when a dyed sample is submitted to him to 
select the coloring matters required for the production of the 
respective color. With a mixture of solutions prepared in ac- 
cordance with the method given above he may make an ex- 
periment, and from the shade obtained he will at once know 
whether he has hit the proper proportion or whether there is 
too much of one or the other coloring matter, and in most 
cases scarcely more than two trials will be required in order to 
imitate even the most difficult colors. 

When working with ready-made dye-stuffs, for instance ani- 
line colors, it is best, on account of their great coloring power, 
not to prepare the standard fluids in the above-described man- 
ner by making a saturated solution in water and then diluting 
the solution. A solution of water-soluble blue prepared in 
that manner would, for instance, appear black, and require 
enormous quantities of water for dilution to make a fluid suita- 
ble for dyeing. For this reason it is preferable to weigh out, 
according to the coloring power of the dye-stuff, a certain 
quantity of it, say, o.i, 0.3, 0.7, and so on, to 3 ounces, and 
dissolve this quantity in 1 quart of water. Mark the solution 
thus obtained with 100, as being the most powerful color, and 
mix aV» A» 2V. and so on > quart of it with £$, |-f , ££, and so on, 
quart of water. 

TONING FLUIDS. 

In many dyeing establishments it is customary to treat the 
leathers, after the application of the mordants, with solutions 
of copperas, sulphate of zinc or sulphate of copper, or of alum, 
potassium chromate, etc. This operation may suitably be 
called toning the colors, and the fluids used for the purpose, 
toning fluids. 

The mode of action of the toning fluids varies much accord- 



THE DYEING OF LEATHER. 579 

ing to the constitution of the leather and the coloring matter 
used, and in certain cases may be designated as the actual 
development of the color itself, while in others it simply 
causes a corresponding change in the constitution of the tone 
of color. It may here be remarked that colors produced with 
the use of aniline colors alone, do not require toning. 

If, for instance, a leather has been treated with logwood de- 
coction, only a pale gray-blue coloration is obtained, the blue- 
black color appearing only after pouring copperas solution 
over the leather. In this case it may be said that the toning 
fluid exerts a dyeing action, and it might also be designated 
as a developing fluid. 

A toning fluid consisting of potassium chromate solution 
acts in a similar manner, a deep black being immediately 
produced when applied to leather dyed with logwood. If 
tanned leather be brought in contact with a fluid containing 
copperas, it is immediately colored bluish-blackish and, with 
the use of more concentrated copperas solution, even deep 
black, the reason for this being that the copperas forms a 
black combination with the tannin. Hence copperas can be 
used as toning fluid upon tanned leather, or upon leather dyed 
with color containing tannin when very dark, nearly black 
tones are to be produced. Moreover, it may here be re- 
marked that every color, no matter with what toning fluid it 
may be treated, becomes darker in consequence of such treat- 
ment. Alum solution when used as a toning fluid, however, 
is to a certain extent an exception, since it serves the purpose 
of fixing upon the surface of the leather any non-fixed color- 
ing matter present. Regarding the toning fluids in general, it 
may be remarked that great care must be observed in using 
them in their more concentrated state, otherwise the resulting 
tones will be too dark. 

Toning fluids may be prepared in the following proportions : 

No. i . Alum 2.5 

Water 100. 



580 THE MANUFACTURE OF LEATHER. 

No. 2. Alum 5 

Water ioo 

No. I. Copperas I 

Water ioo 

No. 2. Copperas I 

Water ioo 

No. 3. Copperas 3 

Water 100 

No. 4. Copperas 4 

Water 100 

Remarks : No. 3 serves for deep gray and black-blue, No. 4 
exclusively for black. 

No. I. Sulphate of copper l. 

Water 100. 

No. 2. Sulphate of copper 2. 

Water ioo. 

No. 3. Sulphate of copper 3. 

Water 100. 

No. 1 . Sulphate of zinc 2.5 

Water 100. 

No. 1. Potassium chromate 0.5 

Water 100. 

Remarks : The latter fluid only for logwood and black. 

THE COLOR MIXTURES. 

On account of the variations in the chemical constitution of 
the different kinds of leather, the color-mixtures used in dyeing 
must be different for every variety of leather, and we will here 
give the most important directions regarding the respective 
proportions for the different kinds of leather. 

Genuine Russia Leather. — This leather is generally dyed only 
two colors, either black or red. 

Black is produced by mordanting with alum and copperas, 
and subsequent treatment with logwood decoction. 

Red is produced by mordanting with alum and subsequent 
application of decoction of sanders wood. The result of this 
treatment is a quite pure bright red. If the color is to have a 
brown tinge, decoction of logwood may to a limited extent be 
used, together with decoction of sanders wood. 



THE DYEING OF LEATHER. 581 

Russia leather for articles of luxury may be dyed every de- 
sired color with aniline colors, with the exception of the deli- 
cate and pale tones, which demand the presence of a white basis. 

Morocco Leather. — The following dye-stuffs are used for the 
old style of sumac tanned morocco leather — the colors would 
not answer for the modern kid leather unless it be first mord- 
anted with a warm solution of sumac : 

For yellow : Barberries, fustic, or French berries (berries of 
Avignon). 

For orange : Equal parts of decoction of brazil wood and 
fustic, and for toning after the first dyeing with decoction of 
barberries in larger or smaller quantities of alum. 

For red : Decoction of brazil wood only. 

For green : Yellow, according to one of the previously given 
methods, and upon this blue according to the following process : 

For blue: Indigo (soluble), soluble Berlin blue, or Berlin 
blue from yellow prussiate of potash and ferric oxide. 

For brown : Logwood and toning with copperas and alum. 

For black : Logwood, a small quantity of fustic and copperas. 

Cordovan Leather. — The principal colors of this leather as 
found in commerce are yellow, red and black. It is dyed as 
follows : 

Yellow: With French berries and alum. 

Red : With kermis grains and alum. 

Black : With logwood and copperas. 

Chamois Leather. — This leather, when bleached with sul- 
phurous acid, is dyed like tanned leather. If not bleached with 
sulphurous acid it is simply colored rather in a mechanical 
than chemical way, for instance, by rubbing in whiting, ochre, 
as well as chrome yellow and reddle. For black, decoction of 
gall-nuts is used and afterwards acetate of iron. 

Tawed Leather. — On account of its white color and its con- 
tent of alum, which does not exert an injurious effect upon the 
most delicate shade, this leather can be dyed almost any color. 
The dyeing of tawed leather has been greatly simplified by the 
extraordinary beauty of the aniline colors and the facility with 



582 THE MANUFACTURE OF LEATHER. 

which they adhere to the leather, it being only necessary to 
prepare a solution of proper concentration of the dye-stuff. 
However, for certain undecided colors, especially for the 
various grays, browns and brown-greens, the aniline colors are 
not very suitable, although the respective tones may be pro- 
duced with them. We will, therefore, briefly mention the dye- 
stuffs required for dyeing tawed leather according to the old 
method. 

For yellow : Barberries, fustic, chrome yellow, for delicate 
yellow also weld. However, at present, picric acid is most 
frequently used, and with it, according to the concentration of 
the solution, every shade of yellow can be produced. 

For red : For dark red, brazil wood in concentrated form 
and alum toning fluid ; for lighter shades to delicate, rosewood, 
dilute decoction of brazil wood, as well as cochineal. At 
present a fine quality of fuchsin is most frequently used for 
delicate red. 

'For green : Yellow as above, and blue. For the pure color 
alone aniline green is now frequently used and besides for 
broken green, logwood. Pale green (water green, Nile green) 
is produced with soluble indigo and picric acid. 

For blue : Soluble indigo, Berlin blue from yellow prussiate 
of potash and copperas. 

For violet: Red as above and soluble indigo; or directly 
methyl violet or for broken violet fuchsin and logwood. 

For brown : Logwood, Brazil wood and fustic in various 
mixtures. 

For gray : The same dyestuffs as for browns, only in differ- 
ent proportions. 

For black: Logwood (with or without Brazil wood) and 
potassium chromate or copperas (also acetate of iron). 

For all the dye-stuffs mentioned above the aniline colors offer 
the best substitute. It is, however, by no means necessary to 
provide the numerous preparations which are found in com- 
merce under all kinds of names, and generally are nothing else 
but a well-known color under a new name. 



THE DYEING OF LEATHER. 583 

From the dye-stuffs above mentioned all the colors required, 
especially in dyeing kid, can be readily compounded. How- 
ever, in buying the dye-stuffs care should be taken to select the 
finest qualities, even if comparatively dear, since actually pure 
tones can only be obtained with them. The correctness of this 
advice can be readily proved. There occurs in commerce, for 
instance, a fuchsin or an aniline violet which is much cheaper 
than other preparations of the same kind, and in a solid state 
as well as in concentrated solution shows no apparent differ- 
ences from the better qualities ; both the cheap as well as the 
more expensive dye-stuff yielding beautiful red or violet solu- 
tions. 

In making, however, a dyeing test with both preparations, 
the difference becomes immediately apparent, the more ex- 
pensive fuchsin yielding a pure fiery red, while with the cheaper 
article it is impossible to obtain the same result, the tones 
always appearing veiled with yellow or brown admixtures. 
The two kinds of violet behave the same way in dyeing. The 
cause of this phenomenon is found in the fact that the cheap 
preparations have not been freed by recrystallization from ad- 
mixed products which have been formed, besides the actual 
coloring matter, in the preparation of the fuchsin or violet, and 
these products possessing also the power of dyeing exert an 
injurious effect upon the pure color. With the extraordinary 
dyeing power of the aniline colors it would be false economy 
to buy the cheaper qualities, since it is impossible to obtain 
with them pure colors. 

The most important dyes of the group of the aniline colors 
are picric acid, fuchsin, water-soluble blue, methyl violet and 
iodine green. 

For pure colors without toning, the above mentioned colors 
are used by themselves, and by suitably diluting the solutions 
the strongest colors may be produced, as well as those which, 
like a breath, simply modified the white basis color of the 
leather to yellowish, reddish, bluish, etc. 

For colors which are formed by mixing two coloring matters, 



584 THE MANUFACTURE OF LEATHER. 

mixtures of the solutions of these coloring matters can be 
directly employed. Thus for orange, picric acid and fuchsin 
are used, for green, picric acid and soluble blue, for violet, 
fuchsin and soluble blue, and by allowing one or the other 
coloring matter to predominate, various shades of the respect- 
ive mixed color may be obtained. 

Since the blended colors, brown and gray, may also be com- 
pounded from the three primary colors, yellow, red and blue* 
and the latter in their greatest purity are represented among 
the aniline colors by picric acid, fuchsin and water-soluble blue, 
the blended may also be prepared by mixing these three primary 
colors. With the assistance of aniline salts, pure black may 
also be produced, and hence it maybe said that in an establish- 
ment in which aniline colors are exclusively used, all tones of 
colors can be obtained which otherwise are produced with the 
aid of the various coloring matters of vegetable and animal 
origin. 

In many establishments for dyeing leather it is customary to 
use aniline colors besides coloring matters obtained from woods 
or other vegetable substances, the aniline colors for economical 
reasons being, as a rule, employed only for brightening the 
colors. By taking, however, into consideration the cost of the 
coloring matters and the extra labor involved, it will readily be 
seen that dyeing with aniline colors is not more expensive, so 
that it may also be recommended from this point of view. 

PREPARATION OF THE LEATHER FOR DYEING. 

The leather to be dyed must be carefully inspected and 
sorted, since every kind of leather cannot in the same manner 
be used for dyeing. Leather which is not of uniform density 
does not take the dye in a uniform manner, and no matter how 
carefully the work may have been done, the product will turn 
out spotted or cloudy. For sorting the leather to be dyed, 
practical experience is of the utmost importance. The work- 
men entrusted with the work must know, without much hesita- 
tion, by the feel and appearance of the skins, what is to be done 
with them as regards dyeing. 



THE DYEING OF LEATHER. 585 



SORTING. 



The principal point to be observed in sorting morocco and 
cordovan leather for dyeing is uniformity and softness of the 
skins. Very light colors are not applied to these varieties of 
leather. In sorting chamois leather which is to be dyed, the 
skins distinguished by special uniformity are also selected. 

The most difficult task is the sorting of tawed leather, espec- 
ially the small skins intended for glace leather. It is, for in- 
stance, well known that gloves the color of which shows very 
slight defects are thrown out as seconds, and the dyer who does 
not desire to produce a large quantity of them must learn to 
avoid even very small blemishes. 

Leather which when dyed delicate colors would give many- 
seconds, may, however, be utilized for dark colors, but the 
latter must be the darker the more pronounced the defects are. 
In sorting it is, therefore, best to separate the skins into several 
classes and dye accordingly. 

The first class might comprise the leather which is not to be 
dyed, but intended to be worked into white ball-gloves. Beside 
a very fine and smooth grain, this leather must be distinguished 
by special softness and pliability. Such skins are simply 
bleached, if necessary blued, and mechanically worked to im- 
part to them uniform thickness and luster. 

The second class might embrace the leather which besides- 
possessing softness and pliability, is perfectly free from blem- 
ishes. Such leather is used for the most delicate colors, such 
as straw yellow, pearl gray, pale brown, as well as for blue with 
aniline colors. 

The third class might comprise the leather which shows such 
small defects as might be very prominent with light colors, but 
disappear with darker colors. Such skins are dyed dark gray r 
dark brown, but especially blended colors, such as date color r 
olive green, etc. 

The fourth class might include leather with more serious de- 
fects than the foregoing, and the grain side of which is not 



586 THE MANUFACTURE OF LEATHER. 

quite smooth, but which nevertheless possesses softness and 
pliability. Such leather is, as a rule, dyed black. 

Finally, the fifth class might embrace the leather which 
shows grave defects and an uneven grain, less pliability, and a 
non-uniform thickness. Such leather is always dyed black. It 
is seldom worked into gloves, but chiefly utilized as fine shoe 
leather. 

WASHING THE SKINS. 

In the subsequent operation to which the sorted skins are 
subjected, it is advisable to handle at the same time only skins 
belonging to the same class, since in consequence of their 
uniformity they behave, as will be readily understood, in the 
same manner throughout these operations, whereby the work is 
essentially facilitated. 

The first operation which actually belongs to the preparation 
of the skins is washing. The chief object of washing tanned 
skins is to remove mechanically adhering dust, to dissolve an 
excess of tannin which is not firmly fixed upon the fiber, and 
uniformly to moisten the skins so that in the subsequent 
mordanting and dyeing, the mordant as well as the dyeing 
liquid can penetrate to a certain depth into the leather, thus 
making the color more solid and more durable. The skins to 
be cleansed are first spread smoothly on a table, which should 
be perfectly level, and treated with wet brushes. They are 
then placed in water of 68° to yy F., and allowed to remain a 
few hours until the water has acquired a brownish color from 
the dissolved substances. The skins are then transferred to 
clean water, in which they remain until they have acquired the 
proper degree of softness. They are then taken out and, when 
quite dry on the surface, subjected to the operations of mor- 
danting and dyeing. 

Much greater care has to be exercised in washing tawed 
leather which is to be worked for glace leather. Small particles 
of the alum and of the nourishing paste used in tawing adhere 
to the surface of the skins and are also imbedded in the pores. 



THE DYEING OF LEATHER. 587 

We know that alum possesses the property of fixing coloring 
matters. Now if some portions of the skin have retained more 
alum than others, more coloring matter will be precipitated 
there and the dyeing will not turn out uniform all over. By 
examining with the microscope colored leather not sufficiently 
washed previous to dyeing, a number of darker spots due to a 
heavier fixation of coloring matter on the places richer in alum 
will be plainly seen. 

According to the opinion of many dyers the object of wash- 
ing is to remove as much alum as possible from the leather. 
However, in our opinion this idea is not correct, since the un- 
avoidable consequence of the partial extraction of tawing 
matter would be that the outer portions of the leather thus 
treated would, in drying, shrink in a different manner from the 
interior portions from which the tawing matter has not been 
withdrawn, and the leather would not acquire the beautiful 
luster of leather not subjected to this treatment. It may here 
be remarked that this error can never be entirely corrected by 
the subsequent treatment with nourishing paste. Hence the 
leather should only be washed sufficiently to remove any excess 
of alum. It can then be readily and uniformly dyed and with- 
out trouble be converted into actual glace leather, i. e., leather 
with great luster. 

For washing lukewarm water is used, a number of skins to 
be dyed — 30 to 50 dozen — being generally treated at one time. 
To assure uniform moistening of all the skins it is best to use 
a large vat. One skin after the other is then immersed in the 
water, moved to and fro, and spread out smoothly on the 
bottom of the vat. 

For the uniform and vigorous washing of the skins it is 
necessary to subject them to a certain mechanical pressure, 
and it is generally done by workmen treading them with their 
bare feet. It will be readily understood that the process is 
quite primitive and, as manual labor has to be used, also quite 
expensive. However, notwithstanding these drawbacks, which 
are perfectly understood by most dyers, many of them assert 



5' 



THE MANUFACTURE OF LEATHER. 



that the treading of the skins cannot be replaced by any other 
method of manipulation, and that only in this manner can the 
skins be prepared for uniform dyeing. 

THE WASHING MACHINE. 

The above-mentioned assertion is, however, incorrect, since 
the work of washing and proper manipulation may be executed 
with the assistance of mechanical appliances, the arrangement 
shown in Fig. 144 being well adapted for the purpose. The 
skins to be washed are hung together by twine drawn through 
holes in the foot pieces. However, since fresh twine would be 
required for each operation it has been endeavored to substi- 
tute another material for it, quite thin, well-tinned iron wire, 
bent to a hook of the form of an S, being found the most suita- 
ble for the purpose. It is absolutely necessary that these 

Fig. 144. 




hooks should be thoroughly tinned, since if the skin comes in 
contact with the iron itself, that portion would, in the subse- 
quent dyeing, turn out spotted. Hence the hooks must be 
closely inspected, and any one which shows the bright iron 
through the tin coating immediately removed. 

The apparatus consists of two vats (AT and Kj). Into one 
of these vats the skins are brought as follows : The first skin is 
laid, flesh side down, and upon it, connected with it by hooks, 



THE DYEING OF LEATHER. 589 

is placed the second skin, grain side down ; upon this is laid 
the third skin, flesh side down, and upon the latter the fourth 
skin, grain side down, and so on. Above the vat {K) are 
fixed a few guide rolls and alongside of it are standards carry- 
ing two rolls (B and B f ). These rolls may be revolved in 
every direction, and their peripheries are furnished with bristles 
so that they actually form cylindrical brushes. In order to 
press the two rolls with a certain force against each other, a 
block of wood (H) is placed over each end of the axle of the 
upper roll. The blocks of wood are connected by a cross 
piece which carries a wooden box filled to a suitable depth 
with sand, whereby a moderate pressure is exerted. Along- 
side the standards carrying the brush rolls (B and B T ) are 
similar standards in which rest two wooden cylinders (Cand C f ) 
of equal size, the surfaces of which are covered with vulcanized 
rubber. These rolls can be pressed together by means of a 
screw. To one of the rolls is fixed a crank as well as a pulley, 
the latter being connected by means of a belt with a pulley on 
B, so that both rolls must move simultaneously. The vat (Kj) 
is also provided with guide rolls arranged in the same manner 
as those on K. 

When the skins have in the above described manner been 
placed in the vat, sufficient water to cover them is admitted, and 
they are then allowed to stand quietly for one hour. To avoid 
the formation of air-bubbles between the separate skins it is 
recommended to admit the water through a rubber hose while 
arranging the skins in the vat, and to regulate the flow of water 
so that the skins placed last are covered about one-half inch 
deep with water. If the skins have been properly brought into 
the vat they will be uniformly moistened in about one hour, 
and the mechanical manipulation may be proceeded with as 
follows : Lift the uppermost skin from the vat, push it between 
the brush-rolls (B and B f ) and set the crank on the roll (C) 
in motion. The skin as it emerges from between B and B z is 
pushed with the hand between the rolls ( C and C z ). By 
the brush-rolls the entire surface of the wet skins is uniformly 



59° THE MANUFACTURE OF LEATHER. 

brushed, and adhering particles of nourishing paste and of 
alum are removed. Where plenty of water can be had it may- 
be recommended to arrange pipes perforated with small holes 
below the lower, and above the upper roll, and squirt water 
through them upon the skins. While such arrangement is not 
absolutely necessary, it facilitates the work. 

As will be seen from the arrangement of the apparatus, the 
skins which have been manipulated between B and B T must 
pass between C and C n and are there subjected to a uniform 
and quite strong pressure, so that not only the water adhering 
to the surface, but also a portion of the water absorbed by them 
is withdrawn. 

The skins having thus been quite vigorously expressed now 
reach the vat (K z ). The progress of the work should, how- 
ever, be so regulated that the workman who has charge of the 
vat (K T ) has sufficient time to arrange the skins in it in the 
same manner as they were originally arranged in K, water 
being admitted at the same time. 

In placing the skins in the vat (J£ T ), those which were on 
top in K come now on the bottom, which is of great advantage 
for the uniformity of the work, since the skins on the bottom 
are evidently subjected to the pressure of a higher volume of 
fluid than those on top, and are consequently soaked through 
in a much shorter time. When all the skins have in this man- 
ner been brought into the vat (Kj), they are allowed to re- 
main in it for one hour. The belt is then detached from the 
two pulleys, and the contrivance carrying the brush-rolls (B 
and B T ) is so placed that it stands between the rubber-faced 
rolls (C~and C z ) and the vat {K T ). The belt is then thrown 
upon the pulleys, and by revolving the rolls the skins are con- 
veyed back to the vat (K). 

If it is desired to manipulate many skins at one time, the vats 
(K and Kj) would have to be quite deep, which is, however, 
inconvenient for arranging the skins. It is therefore preferable 
to give the vessels the shape of a trough rather than that of a 
vat, so that four to six skins may be placed alongside one 
another. 



THE DYEING OF LEATHER. 591 

Every time after the skins have been lifted from either of the 
vats, the water must, of course, be discharged. In dyeing es- 
tablishments connected with a tannery the first wash water, 
which contains a certain quantity of alum in solution, may be 
used for dissolving the alum used in tawing. 

One of the most important questions which arises is, how 
long must washing be continued? To answer this question 
properly it is necessary to enter somewhat into the considera- 
tion of the condition of leather. 

According to the opinion prevailing at present regarding 
the nature of the tanning process, tanning is effected by the 
tanning agent — in this case alum — enveloping the fibers of 
which the skin-tissue consists and preventing the leather from 
becoming hard in drying, the nourishing paste co-operating 
thereby in the same manner. Hence the alum is deposited 
upon the fibers of the skin simply by surface-attraction, but if 
tawed leather be brought in contact with water the dissolving 
power of the latter overcomes the surface-attraction, and alum 
is removed from the surface of the fibers. Hence if a piece of 
tawed leather is allowed for some time to remain in water 
which is frequently changed, it can be completely freed from 
tanning material; i. e., reconverted into raw skin. By drying, 
such leather shrivels up to a hard, tough mass similar to raw 
skin, and if kept constantly moist, becomes finally putrid. 

Of course, washing will never be carried to such an extent 
as to free the leather completely from tanning material. It 
must, however, be taken into consideration, that if washing be 
continued even somewhat too long, the surface may be partially 
divested of tanning material; and this has the double disad- 
vantage that, in order to obtain leather of a proper degree of 
softness, an exceedingly large quantity of yolk of egg has later 
on to be used as nourishment, whereby the expense of produc- 
tion is unnecessarily increased, and besides a special alum- 
mordant has to be applied previous to actual dyeing, as other- 
wise there would not be sufficient alum upon the surface of the 
leather to fix the coloring matter. The latter difficulty is of 



592 THE MANUFACTURE OF LEATHER. 

less importance in dyeing with aniline colors, they being sub- 
stantive upon animal fibers; i. e., they combine with them 
without previous mordanting, though they also adhere better 
when alum- mordant is present. Besides, in dyeing very deli- 
cate colors, for instance, straw-yellow or pearl-gray, the dyeing 
liquor has to be used in a very dilute state, and the small quan- 
tity of coloring matter is partially fixed by the alum still 
present in the leather and partially by the toning fluid used 
after the application of the dye. Hence, leather intended for 
very light colors may be washed somewhat longer than leather 
to be dyed dark, though regarding the latter a factor to be 
immediately discussed has to be taken into consideration ; 
namely, if leather is to be dyed by the dipping process ; i. e., 
by dipping it in the dyeing liquor, it will, of course, be dyed 
upon both sides. This, however, is not desirable, since leather 
to be used for gloves, especially if dyed somewhat darker 
colors, would stain the skin and hence would not be available 
for that purpose. Hence, leather to be dyed by dipping should 
be washed to such an extent that the lower side fixes but a 
very small quantity of coloring matter, not sufficient to stain 
the hand, even if the upper side is dyed very dark. 

From the explanations given above, the following rules in 
reference to washing leather may be deduced : 

i. Leather to be dyed by the application of aniline colors 
should only be washed sufficiently to free the side to be dyed 
from mechanically adhering particles of nourishing paste and 
small crystals of alum. 

2. Leather to be dyed by dipping should be washed until 
the lower side contains but very little alum, so that it will take 
only a small amount of coloring matter. 

3. Leather to be dyed very delicate colors, either by dipping 
or brushing, may be washed longer. 

4. The longer the leather has been washed, the more 
nourishing paste must be given in order to render it again 
sufficiently pliant. 

It is scarcely necessary to give a fixed time required for 



THE DYEING OF LEATHER. 593 

washing, since this depends largely on the nature of the skins 
to be washed and on the temperature of the wash water. The 
denser the leather is and the colder the water used, the longer 
the washing will have to be continued, since under these condi- 
tions it takes more time to moisten the fibers to a certain depth 
and to dissolve a corresponding quantity of alum. Hence for 
washing denser and stouter leather it is best to use somewhat 
warmer water, to shorten the time required for the operation. 
On the other hand, for thin, spongy skins water of the ordinary 
temperature should be used and great care observed in the 
operation. As previously stated the time required for washing 
cannot be given, it depending entirely on practical experience. 
The dyer must ascertain by tests, which he makes with the 
skins, how long washing may suitably be continued. Such ex- 
periments are worth far more than working according to a 
fixed time, which can be correct only in a certain case. 

QUALITY OF THE WATER. 

A few remarks may here be made regarding the quality of 
the water to be used in washing and dyeing leather. The 
water must of course be perfectly clear. If after standing for 
some hours in a large bottle it deposits only a trace of solid 
substance, it is unfit for our purposes and has to be subjected 
to filtration, which will be referred to later on. 

The chemical constitution of the water is also of considerable 
importance to the dyer. Many well waters, as is well known, 
are very hard, i. e., they contain large quantities of calcium car- 
bonate in solution, which causes the separation of aluminium 
hydrate from the alum ; and in case somewhat more alum be 
present on one portion of the leather than on another, more 
aluminium hydrate will remain behind, whereby that portion 
becomes darker, and the leather, consequently, spotted. 

Such water can scarcely be used in washing and dyeing, but 
where no other can be had, it should be boiled before use, or 
what is more suitable for the large quantities required, com- 
pounded with soda solution. The soda renders the calcium 
38 



594 



THE MANUFACTURE OF LEATHER. 



carbonate insoluble and the water becomes turbid in conse- 
quence. To avoid an excess of soda it is best to determine 
once for all the quantity required to separate all the calcium 
carbonate from say fifty gallons of water, and to use a propor- 
tional quantity. Bring the water into a large vat, stir in the 
soda solution, allow to settle and then draw off the clear water. 

Borax should be used in preference to soda for softening the 
water, as it is one of the gentlest of the alkalies and is at the 
same time a fine mordant. One-half pound of borax is gener- 
ally used to one hundred gallons of water. The borax is dis- 
solved in boiling water and added under vigorous stirring. If 
the water is very hard a little more borax will be required. 

For filtering turbid water Forster's sandstone filter shown in 
Fig. 145, is very suitable. It consists of a hollow sandstone 

Fig. 145. 




cylinder (C) having a clear diameter of 4 inches and a length 
of 8 inches. The cylinder is cemented in a cast iron lid, the 
latter sitting upon a sheet iron jacket inserted below in an iron 
foot. The water to be filtered passes under a certain pressure 
from the lower portion of the apparatus, at W, into the jacket 
(M), permeates through the pores of the sandstone cylinder 
(C) and runs off through the lid on top. When the pores of 
the cylinder are clogged up by solid substances to such an ex- 



THE DYEING OF LEATHER. 



595 



tent that filtration proceeds slowly, the cylinder is replaced by 
a new one, and cleansed by turning or grinding the surface. 

If the water contains a considerable quantity of organic sub- 
stances, the production of certain delicate colors with it is next 
to impossible, and in order to render it fit for use it has to be 
filtered through so-called plastic coal. The latter consists of 
animal charcoal dust or meal which is made into a paste with 
glue water. This paste is given definite shapes by moulding 
and the cementing agent destroyed by heating. The plastic 
coal generally has the form of a low hollow cylinder, and a 
number of such cylinders, for instance nine, sixteen, etc., are 
combined to a filtering battery, as shown in Fig. 146. 



Fig. 146. 




Each cylinder is about 8 inches in diameter and 4 inches 
high. The cylinders are connected with each other by short 
pieces of iron pipe. The lowest cylinder, with its pipe, is 
screwed to the false bottom of the vat and is connected with 
the uppermost by means of a rubber hose, which projects 
above the level of the water. With a filter of this construction, 
not only turbid water can be filtered clear, but it is also freed 
from organic substances in solution, the animal charcoal pos- 
sessing the property of absorbing and retaining such substances. 



NOURISHING. 

No matter how much care may have been exercised in wash- 



596 THE MANUFACTURE OF LEATHER. 

ing, the leather will always be somewhat hard if its original 
pliancy is not restored by the so-called nourishment. 

For the nourishment of fine glace leather, yolk of eggs is, 
as a rule, used, the effect of the fat, called egg-oil, contained in 
it, being such as to keep the leather pliable after drying. 
Chemically, yolk of egg consists of vitellin, a peculiar body be- 
longing to the group of albumens, further fat and fat-like bodies 
(cholesterin, lecithine) and a special yellow coloring matter — 
lulein — and potassium salts. For our purposes, however, the 
effective body of the yolk of egg is the fat, which is in a state 
of emulsion, i. e., in the form of very small drops suspended in 
the fluid. Since alkalies also possess the property of convert- 
ing fat into an emulsion, it is recommended to use, besides yolk 
of egg, very small quantities of soda, but not more than about 
8 grains for each yolk. 

The quantity of yolk of egg to be used for a dozen skins de- 
pends on the size of the latter, and whether they have been 
washed more or less. It can only be said that from 3 to 12 
yolks will have to be used for a dozen skins. 

Besides oil of egg, the use of glycerin has been found to give 
excellent results, the leather acquiring great pliancy, since 
glycerin possesses the property of not drying up. 

The operation of nourishing is effected in a vat capable of 
holding about ten dozen skins. Fill the vat about half full of 
water and stir in the yolk of egg so that a uniform milky fluid 
is formed. This is best effected by beating up the yolks of egg 
in a special vessel with water, adding about three drachms of 
glycerin for each yolk of egg used and mixing the whole with 
the water in the vat. The washed skins being well squeezed 
are best suspended to cross-pieces by pairs so that the sides not 
to be dyed touch each other, it being of chief importance that 
the side to be dyed be provided with nourishment. The skins 
are allowed to remain in the vat twelve to fourteen hours and, 
as a rule, they will have absorbed all the nourishment. Should, 
however, any of the latter remain after lifting the skins from the 
vat, it is used in the preparation of a fresh supply. 



THE DYEING OF LEATHER. 597 



PRESERVATION OF YOLK OF EGG. 



The price of yolk of egg being subject to great fluctuations, 
it being, for instance, much lower in the spring than in the fall, 
a mode of preserving it for any length of time may here be 
given. Prepare for this purpose a concentrated solution of 
salicylic acid in water by adding 2^ drachms of salicylic acid 
to one quart of water in an enameled pot, then heat to boiling 
with constant stirring, and allow to cool. Salicylic acid re- 
quires about 300 parts of water for solution, and in cooling a 
portion of the acid is again separated and used in preparing 
fresh solution. 

The eggs, the yolks of which are to be preserved, are opened 
and the yolks and whites carefully separated. The whites 
may in a fresh state be directly sold to cloth-printers, or they 
may by drying upon zinc sheets at 136 F. be converted 
into a solid mass, which may be kept for a long time. The 
yolks are brought into a vessel and intimately mixed with 
salicylic acid solution, one quart of the latter being used for 
three quarts of the former ; thorough stirring and mixing being 
absolutely necessary for proper preservation. The resulting 
milky fluid is stored in a cool place in large glass bottles, which 
are closed with parchment papers soaked in the salicylic acid 
solution. 

Yolks thus preserved with salicylic acid may be kept for 
months without suffering alteration. In dyeing, the acid exerts 
no influence whatever, except with the use of iron salts it would 
produce a red color. 

Lanolin or wool-fat is particularly well adapted for leather 
nourishment, it imparting to the leather great pliancy. Lano- 
lin possesses the characteristic property of mixing with an 
equal quantity by weight of water without losing its fatty nature. 
The "degras" used so largely in the currying of grain and 
split leathers is really lanolin — made from wool fat. 



598 THE MANUFACTURE OF LEATHER. 

DYEING TAWED LEATHER ( GLACE LEATHER). 

The leather may be dyed either by the so-called dipping 
process or upon the board. In the dipping process the leather 
is immersed in the dyeing liquor, and, according to the old 
method, treated by treading with the naked feet until it has 
almost entirely absorbed the coloring matter. In modern 
times this crude method has been replaced by suitable apparatus. 

In dyeing upon the board, only one side of the leather is 
actually dyed, the lower side, when the work is properly done, 
remaining almost entirely white. The operation is executed by 
applying the dyeing liquor to the leather spread on a level 
surface, and immediately bringing the leather into the dyeing 
chamber. In modern times the dipping process has been 
almost entirely replaced by dyeing on the board, since the 
aniline colors which are now almost universally used are sub- 
stantive colors, and the leather would be dyed equally strong 
on both sides if the dipping process were used. The latter 
method is, however, still employed for leather to be dyed pale 
tones with the use of dyeing liquors. 

DIPPING PROCESS. 

The older method of executing this process is as follows : 
The lukewarm dyeing liquor is brought into a vat and a 
number of skins, with the side to be dyed up, are introduced. 
A workman then enters the vat and by moving to and fro with 
his naked feet, endeavors to keep the skins as well as the dye- 
ing liquor in constant motion. In the commencement of the 
operation the dyeing liquor becomes rapidly lighter, the color- 
ing matter being quickly fixed by the leather. When the dye- 
ing liquor is exhausted to such an extent as to be plainly 
visible, a certain quantity of fresh dyeing liquor is poured into 
the vat and treading continued until the pale appearance of 
the dyeing liquor indicates that the coloring matter has been 
fixed. Fresh dyeing liquor is then again introduced and the 
treading and adding of fresh dyeing liquor continues until the 
desired tone of color is obtained. 



THE DYEING OF LEATHER. 



599 



It will be readily understood that before each addition of 
fresh dyeing liquor one of the skins has to be taken from the 
vat and its color compared with the sample, as otherwise the 
tone of color might become too dark. It is therefore recom- 
mended to make an accurate note of the quantity of dyeing 
liquor required to dye a definite number of skins a certain 
shade of color, according to a sample book kept in the estab- 
lishment. The data thus obtained are then strictly adhered to 
with slight modifications depending on the size of the skins to 
be dyed. 

It seems to be suitable to use a simple dipping apparatus 
with the assistance of which one workman can manipulate with- 
out great exertion a large number of skins at one time. Such 
a dipping apparatus is shown in Fig. 147. 

Fig. 147. 




In a vat of the form shown in the illustration revolves a 
wooden wheel. This wheel is of sufficient width that a skin of 
a certain size can be fastened by the forefeet to two nails pro- 
jecting from the surface of the wheel. For working on a 
larger scale the wheel is given the form of a drum, and suffi- 
cient width to suspend three or four skins alongside each other. 
If, for instance, the wheel is 6}4 feet in diameter its circumfer- 
ence is nearly 20 feet, and to such a wheel, which is only wide 
enough for one skin, about sixty skins can be suspended ; to a 
wheel with two widths 120 skins, and so on. The nails or 



600 THE MANUFACTURE OF LEATHER. 

hooks to which the skins are suspended consist of tinned iron, 
and are bent so that the skins secured to them cannot drop off 
when the wheel revolves. These nails or hooks are placed at 
a distance of 3 ^ inches from each other. The skins are sus- 
pended to the nails with the sides to be dyed in front. 

The reservoir (£) is placed at a higher level, and contains 
the dyeing liquor. The pipe (R) issuing from the bottom of 
the reservoir is divided into two branches which run along the 
side of the vat to the centre and then branch off at a right angle. 
The portion bent downward is provided with narrow perfora- 
tions. For discharging the fluid, the lower part of the vat is 
provided with a pipe furnished with a stop-cock. 

The manner of operating this apparatus is very simple. The 
vat is filled with sufficient water so that the skins are moistened 
on revolving the wheel. In order to moisten every skin the 
wheel is allowed to revolve once and the stop-cock on the 
reservoir (£) is then opened to admit the dyeing liquor. The 
wheel is now kept constantly revolving. One skin after the 
other dips into the dye bath and after absorbing a certain 
quantity of the coloring matter is lifted from the bath, thus 
assuring uniform treatment of each skin. When dyeing is 
almost completed, the pipe admitting the dyeing liquor is 
closed either partly or entirely, and after revolving the wheel a 
few times more, the bath is discharged from the vat. The dyed 
skins are taken one after the other from the wheel and brought 
into the drying chamber. 

The use of this apparatus offers the advantage that not only 
a considerable number of skins can be treated at one time, but 
also that the progress of the dyeing operation can at every 
moment be inspected, since a certain number of skins are con- 
stantly lifted from the bath. 

When the skins have been taken from the dyeing liquor they 
are generally brought into a bath of yolk of egg, then pressed 
quite vigorously by passing through between two very smooth 
rolls — the so-called glazing rolls — and brought into the drying 
chamber. 



THE DYEING OF LEATHER. 6oi 



DYEING UPON THE BOARD. 



For dyeing upon the board the following utensils are re- 
quired : A dyeing table, reservoirs for the mordants, dye-stuffs 
and toning fluids and brushes. These utensils should be so 
arranged that the workman can work without interruption, and 
the following arrangement may be recommended as very 
suitable : 

The dyeing table or board should be perfectly level, and the 
plate consist of a material which does not absorb moisture, nor 
exert a chemical action upon the leather. The most suitable 
material for this purpose is zinc, since a sheet of this material 
can be readily secured to a thick wooden plate by bending it 
over the edges of the narrow ends of the latter. The use of 
nails should be avoided. The plate of the table should be 
fixed so as to be about three-fourths inch lower to the right 
than to the left, and on the right-hand narrow side, underneath 
the sheet, a small gutter is provided beneath which a tub is 
placed. 

The fluids required in dyeing should be placed in the order 
used by the workman ; the vessel containing the mordant to 
the left, the vessel with the dyeing liquor in the center, and 
that with the toning liquor to the right. Above the table 
hangs a rubber hose of sufficient size to throw out a jet of 
water the thickness of the thumb, when the cock with which 
it is fitted is opened. Each vessel is provided with a brush 
of soft, quite long bristles and furnished with a handle. Each 
brush should be used only for a certain fluid, and when the 
work is finished be immediately cleansed by thorough washing. 
In place of brushes many dyers use large bath-sponges tied to 
handles. For dyeing it is of course indifferent whether the 
work is done with brushes or sponges, the principal thing being 
the uniform application of the coloring matter. 

The operation of dyeing is commenced by spreading the 
skin to be dyed perfectly smooth on the table and removing 
every wrinkle by gentle rubbing with a rounded off wooden 



602 THE MANUFACTUKE OF LEATHER. 

tool. The mordant is then applied, next the coloring matter, 
and finally the toning fluid. With the use of aniline colors it 
is only necessary to apply the coloring matter. 

To avoid the formation of stains the workman should take 
just sufficient fluid in the brush completely to brush over one 
skin, and he should endeavor to apply the fluid uniformly to 
all portions of the skin. Whether he does this by carrying the 
brush in a spiral line or in a zigzag over the skin is entirely 
optional, the principal thing being that he works uniformly. 

With the use of dye-stuffs obtained from decoctions of vege- 
table substances a mordant consisting of a dilute solution of an 
alkaline carbonate is generally first applied. The action of 
this mordant is as follows : By the alkali, alumina in the form 
of a precipitate is separated from the alum contained in the 
leather, and this freshly precipitated alumina combines very 
rapidly with the coloring matter, so that the latter is more 
completely and more quickly fixed. If sufficient alkali is pres- 
ent it acts also upon the salts used in toning by separating the 
respective metallic oxide, which combines immediately with the 
coloring matter. 

Very dilute solutions of potash or soda are now used, 5 parts 
by weight of potash or soda in 100 parts of water being suffi- 
cient. 

The skin having been uniformly moistened either with the 
alkaline mordant alone, or first with a tin salt mordant and then 
with the alkaline mordant, the dyeing liquor is immediately 
applied, the application being repeated until the desired shade 
of color is obtained, when the work is finished by applying the 
toning fluid. 

When working with aniline colors it is only necessary uni- 
formly to apply the solution of the coloring matter to the skin 
and to repeat the operation until the desired shade is pro- 
duced. 

The dyeing operation being finished, the workman by open- 
ing the cock on the rubber hose allows water to flow over the 
skin, turns it around, and after rinsing the back removes the 



THE DYEING OF LEATHER. 603 

excess of water by vigorously rubbing the back of the skin with 
a tool provided for the purpose. He then spreads the skin, 
dyed side up, on a table standing alongside the dyeing table. 
The skin dyed next is laid, dyed side down, upon the first, the 
third dyed side up, the fourth dyed side down, and so on. 

The workman having dyed a skin rinses the plate with water 
to remove any remaining coloring matter which might discolor 
the back of the next skin, and then proceeds with the opera- 
tion. 

DYES AND TONING FLUIDS. 

The color mixtures which are particularly employed for 
tawed leather have been previously referred to, and but little 
remains to be added. It is considered unnecessary to give 
definite receipts, since they would produce only one tone of the 
respective color, while the modifications of one and the same 
color are very numerous. It is, therefore, decidedly preferable 
to have given to our readers the methods by which a perma- 
nent sample card of colors and their modifications can be ob- 
tained, namely, by systematic dilution of dyeing liquors and 
subsequent mixing. Such colors and modifications once 
determined and entered in the sample book can always be 
reproduced. 

Regarding the aniline colors, it may be remarked that by 
reason of their great dyeing power they should be used only in 
the form of very dilute solutions. Thirty to forty-five grains of 
aniline color dissolved in a fluid are sufficient for the produc- 
tion of beautiful colors, and the dyer by applying twice or three 
times such solutions of moderate concentration can readily 
obtain any shade desired. 

Indigo carmine being next to the aniline colors as regards 
dyeing power must also be used in dilute solution. To avoid 
defects the solutions of aniline colors and of indigo carmine 
should be filtered before use. If, for instance, the dyeing 
liquor holds in suspension a scarcely perceptible solid particle 
of aniline color, the consequence would be that in applying the 



604 THE MANUFACTURE OF LEATHER. 

liquor with the brush, this particle would produce a very dark- 
colored streak, and the coloring of the leather would thereby- 
become defective. 

As dyes, in the actual sense of the word, it is best for colors 
of a pure tone to use aniline colors, namely, for red and its 
modifications, fuchsin ; for yellow, picric acid ; for green, iodine 
green; for blue, indigo carmine or aniline blue; for violet, 
methyl-violet. These colors may be modified by mixing with 
other colors, yellow, for instance, being changed to orange by 
adding red ; red into purple by adding blue, and so on. 

For dying glace leather intended for fancy goods, the use of 
aniline colors may be recommended as most suitable ; but for 
dyeing glove leather blended colors, such as brown, gray and 
olive green, which are at present very much in demand, liquors 
of dye stuffs are to be preferred. 

While formerly the dyer had to use a larger number of dye- 
stuffs in order to obtain a certain shade, at present decoctions 
of fustet, Brazil wood, logwood and alder bark suffice for most 
purposes. The modifications of the colors are effected besides 
with the use of toning fluids by small additions of aniline 
colors, such as picric acid, fuchsin or water-soluble blue, to the 
mixed decoctions. 

DIRECTIONS FOR THE PRODUCTION OF BLENDED COLORS UPON GLACE 

LEATHER. 

A number of receipts are here given according to which the 
most important blended colors, especially those used for glazed 
glove leather, may be prepared. 

The receipts marked II. give colors which may be designated 
the medium shades of the respective colors, while No. I. yield 
very light and No. III. very dark shades. The figures refer to 
units of fluid of the concentrated dye liquors : 

Light ochre yellow and maize yellow, decoction of: 

I. II. III. 

Fustet 25 50 30 

Brazil wood 30 12)^ 1 34 

Logwood \% l2 %, 3 1 



THE DYEING OF LEATHER. 605 

Dark gold ochre to umber, decoction of : 

I. II. III. 

Fustet 6 5 45 

Brazil wood 1% 11 20 

Logwood 5 11 14 

Wood brown to mahogany color, decoction of : 

I. II. III. 

Fustet 35 13 24 

Brazilwood 2 16 4^ 

Logwood 6 5% 53 

Reddish brown to Venetian red, decoction of: 

I. II. III. 

Fustet 7% 25 50 

Brazilwood 5 l l)4. 3° 

Logwood 22 3 3^ 

Brownish red (Pompeian red), decoction of: 

I. II. III. 

Fustet 52 6 50 

Brazil wood 5 26 3 

Logwood 20 11 \% 

Pure Havana brown, decoction of: 

I. II. III. 

Fustet 50 50 50 

Brazil wood 2 7/<j IO 7%, 

Logwood 1 2_^j 7 I 

Sienna brown, decoction of: 

I. II. III. 

Fu stet 50 32^ 9 

Brazil wood 9 8 3 2 3l> 

Logwood 71^ 1 6 

Dark bister brown, decoction of : 

I. II. III. 

Fustet 50 30 50 

Brazil wood 1 71^ 15 

Logwood 2 10 2)^ 



606 THE MANUFACTURE OF LEATHER. 

Olive, decoction of: 

I. 

Fustet 50 

Brazil wood 5 

Logwood 1 

Red brown to dark brown, decoction of: 

I. 

Fustet 15 

Brazil wood 37/4 

Logwood 4 

Green brown to dark brown, decoction of: 

I. 

Fustet 37^ 

Brazil wood 4 

Logwood 6 

Lac brown and dark brown, decoction of: 

I. 

Fustet 52)^ 

Brazil wood 3 

Logwood 6 

Sepia brown, decoction of: 

I. 

Fustet 4- 2 /4 

Brazil wood 2 7/4 

Logwood 18 

Iron violet, decoction of : 

I. 

Fustet 16 

Brazil wood < 36 

Logwood 10 

Gray blue (dark pigeon gray), decoction of: 

I. 

Fustet 25 

Brazil wood 5 

Logwood 25 



II. 


III. 


50 


5 


10 


50 


27% 


10 



II. 


III. 


25 


37K 


25 


I2# 


*7% 


4 



II. 


III 


22^ 


3 


I7M 


3° 


12M 


*S 



II. 


III. 


37>2 


30 


7% 


27^ 


3% 


5 


II. 


III. 


40 


2^ 


3 


™% 


16 


40 


II. 


III. 


27 


50 


14 


1 


6 


6 



II. 


III. 


30 


5° 


9 


15 


32^ 


4 



THE DYEING OF LEATHER. 60/ 

Slate gray, decoction of : 

I. 

Fustet 15 

Brazil wood 10 

Elder bark 50 



II. 


III. 


*5 


35 


15 


5° 


32)4 


50 


II. 


III. 


11 


30 


6 


1 


H 


VX 



II. 


III 


5o 


30 


6 


30 


11 


10 


iU 


2 



Iron or steel gray, decoction of: 

I. 

Fustet 1 

Brazil wood 10 

Logwood 9 

Elder bark 27)0 Z1%. 5° 

Light ash gray, decoction of: 

I. 

Fustet 27)^ 

Brazil wood 8 

Logwood 30 

Elder bark — 

It only remains to give here the toning fluids to be used for 
the different broken colors, and to mention that the numbers 
of the separate fluids are so placed that in this case the higher 
number also produces a deeper tone. 

Mixtures of various quantities of decoctions of fustet, Brazil 
wood and logwood are used for : 

Light ochre yellow, maize yellow to dark gold ochre yellow: 
Toning with alum for the light shades, and with sulphate of 
zinc for the darker shades. 

Light wood brown to sad mahogany color : Toning with sul- 
phate of zinc. 

Havana brown through red to an indefinite olive color : For 
the lighter shades sulphate of copper 1 and 2, for the darker 
shades 3 and 4. 

Lac brown and dark brown, with sulphate of copper 1 and 2. 
• For slate gray in all its modifications : Copperas 1 to 4. 

For iron violet in all its modifications : Sulphate of copper 1 
to 4. 

For reddish violet: Sulphate of zinc. 



<6o8 THE MANUFACTURE OF LEATHER. 

Mixtures of various quantities of fustet, Brazil wood and log- 
wood besides elder bark are used for : 

Stone gray with copperas i and 2. 

Olive green with copperas 1, 2 and 3. 

Gray green with copperas 1 and 2. 

Steel gray with copperas 2. 

Remarks : A quite satisfactory black may also be produced 
by a mixture of decoctions of fustet, Brazil wood and logwood, 
in which the latter should especially preponderate, and with 
the use of a toning fluid containing potassium chromate in 
solution. However, the process does not suffice for the pro- 
duction of a pure lustrous black, and dyeing leather black 
forms a special branch of the glace leather dyeing industry. 

In conclusion it may be added that the above mentioned in- 
structions regarding shades of color and toning fluids refer to 
dyeing upon the board. The lighter modifications of these 
colors, especially ochre yellow* and pale green, may also be 
produced by dipping, but in this case the dye liquor should be 
somewhat darker, as the color is not toned. 

MIXED COLORS. 

This term may be applied to colors produced from a mineral 
color — Berlin and chrome yellow — and an organic dyestufif. 
While these colors were formerly quite frequently used for the 
production of neat effects, they have at present been almost 
entirely abandoned, the aniline colors being by far. more con- 
venient for obtaining the same shades. 

Dyeing with mineral colors is effected by giving a mordant 
consisting of a salt, applying upon this the solution of another 
salt, whereby either pure blue or pure yellow is obtained. 
Now by laying upon the blue pure yellow, green is obtained ; 
by using pure red, violet is formed ; or by laying pure red 
upon chrome yellow, orange — in one word, every shade of color 
may in this manner be obtained, the production of agreeable 
modifications being in this case largely dependent on the skill 
of the workman in harmonizing the colors. 



THE DYEING OF LEATHER. 609 

Thus, for instance, by applying picric acid solution to leather 
dyed with Berlin blue, all shades from pale grass green to dark 
malachite green may be produced ; light olive green upon 
leather dyed with Berlin blue is obtained with quercitron and 
archil. 

In the reverse manner, by applying water-soluble blue to 
leather dyed with chrome yellow, various shades of green may be 
produced, while by the use of fuchsin orange is obtained, by the 
use of elder bark, sallow shades with a grayish tinge, and so on. 

For the production of all these colors the leather has to be 
handled three times, namely, mordanting, dyeing and apply- 
ing the organic coloring matter, while in working with aniline 
colors the desired shade is obtained by one manipulation. 

DYEING LEATHER BLACK. 

Dyeing leather black is by many considered a special art, 
but actually it is not more difficult than any other color, the 
only thing necessary being the proper choice of the dyestuff. 

If a fluid containing tannin in solution, for instance, a decoc- 
tion of tan-bark, gall-nuts, etc., be compounded with an iron 
salt, it is immediately colored deep black, and this process was 
formerly exclusively employed in the manufacture of ink, the 
very delicate precipitate formed in the fluid being held in sus- 
pension by the addition of gum solution. 

By diluting the solutions of the tannin and of the iron salt, 
and pouring them together, it will be observed that the fluid is 
not black, but rather green or blue, and the coloration depends 
on the nature of the tannin used as well as on that of the iron 
salt (ferrous or ferric oxide). The color appears black to the 
eye only when the fluids are in a more concentrated state, but 
always with an admixture of green or blue, so that actually we 
have only a very dark green or blue, but not a black. By 
applying a fluid containing tannin to leather previously mor- 
danted with iron salt (copperas or acetate of iron), a precipi- 
tate is formed, and the leather is colored blue-black or green- 
black. 

39 



6lO THE MANUFACTURE OF LEATHER. 

By adding to a decoction of logwood a very small quantity 
of potassium chromate solution, the fluid is immediately col- 
ored deep black-blue without, however, a precipitate being 
formed. The chemical process of this phenomenon is not yet 
thoroughly understood, but it is supposed that a soluble chrome 
combination of the coloring matter is formed. 

Now this behavior of bodies containing tannin towards iron 
salts or that of logwood decoction towards potassium chromate 
may be utilized for dyeing leather black, but very frequently 
mixed fluids are used. 

DYEING WITH TANNIN AND IRON SALTS. 

This mode of dyeing is seldom used for finer qualities of 
leather, but frequently for shoe leather. For dyeing tanned 
leather it is only necessary to apply the solution to the leather, 
the tannin contained in the latter being sufficient to produce 
coloration. However, as a rule, the leather is first treated with 
a decoction of tanning material, generally of gall-nuts or sumac, 
and then dyed with the iron salt. It is recommended to ascer- 
tain, previously to dyeing, the proper constitution of the solu- 
tion by a small experiment, because with the use of too small 
a quantity of tannin the resulting color will not be dark enough, 
but show a sallow tone. It is also of importance not to use 
more of the iron salt than absolutely necessary, since exper- 
ience has shown that an excess renders the leather brittle. 

DYEING WITH LOGWOOD AND POTASSIUM CHROMATE. 

The solution of the logwood coloring matter may be pre- 
pared either by boiling rasped logwood with water, or by dis- 
solving solid logwood extract in water. In working according 
to the first process it is best to prepare a completely saturated 
solution of the dye-stuff by boiling a large quantity of the 
wood for several hours and straining the solution. However, 
working with solid logwood extract is much more convenient, 
since by a few experiments it can be readily ascertained how 
much water has to be taken for a certain quantity of extract in 
order to obtain a dyeing liquor of the proper concentration. 



THE DYEING OF LEATHER. 6l I 

The leather is treated with the solution of the dye-stuff and 
then brushed over with the solution of potassium chromate. 
For this purpose the toning fluid No. I may be used, but it 
must be suitably diluted with water. 

. By using the solution of logwood extract in a too concen- 
trated state it will be observed that the color acquires a pecu- 
liar metallic luster which should be avoided in dyeing black, 
and this can be done by simply diluting the solution with 
water. 

With proper concentration of both fluids a beautiful black 
with a bluish tinge is immediately obtained. This bluish tinge 
may be heightened by adding to the logwood decoction a 
small quantity of indigo carmine, or by slightly dyeing the 
leather with aniline blue before applying the logwood solution. 

DYEING WITH TANNIN AND LOGWOOD. 

The majority of leather dyers prefer mixtures of the colors, 
which can be produced by tannin and logwood, and there is 
good reason for this preference, because the tannin color is 
generally somewhat greenish and the logwood color bluish, 
while both together, with a little fustic decoction, give black. 

A receipt, according to which, for instance, a very beautiful 
black upon leather may be obtained, is as follows : Boil tan 
ioo parts, logwood 25, fustic 12, water 250. Apply the re- 
sulting liquor to the leather, and then solution of copperas, to 
which a small quantity of nitric acid has been added, or solu- 
tion of acetate of iron. A still better result is obtained by 
adding to the iron solution a small quantity of potassium 
chromate. 

The methods of dyeing black described above may be used 
for tanned, chamois and tawed leather. In dyeing the latter, 
especially thin skins, care must be taken to prevent the dye 
from penetrating the leather, which is best effected by applying 
to the side to be colored, prior to the actual dyeing, solution of 
soda or potash, and by using the dyeing liquor no more diluted 
than is absolutely necessary. 



6l2 THE MANUFACTURE OF LEATHER. 

DEEP BLACK NIGROSIN COLOR. 

Dissolve 40 parts borax in 800 parts water by heating, bring 
gradually into the solution 150 parts pulverized brown shellac 
and boil until all the shellac is dissolved, from time to time re- 
placing the water lost by evaporation. Now triturate 40 parts 
nigrosin (aniline black) with a portion of the solution to a thick 
milky fluid which is finally intimately mixed with the remainder 
of the borax-shellac solution. This preparation, when applied 
with a brush, gives a lustrous, deep black color immediately 
after drying. 

BLUE BLACK NIGROSIN COLOR. 

I. Dissolve in 400 parts water, 30 parts borax and 3 parts 
caustic soda, introduce 1 30 parts brown shellac and boil until 
the latter is dissolved. 

II. Dissolve in 300 parts water, 50 parts logwood extract, 20 
parts aniline deep black, and add 10 parts glycerin. Accord- 
ing to whether the color is to show a more or less blue tinge 
add 5 to 10 parts methyl-blue. 

III. Compound the mixture of solutions I. and II. with 50 
parts of a 20 per cent, acetate of iron solution and 90 parts 
water. 

Actual high lustre is imparted to leather dyed black only by 
the so-called polishing or glossing, and this operation has to be 
distinguished from glazing, to which tawed leather of other 
colors is subjected. 

GLAZING AND GLOSSING OF LEATHER. 

Glazing. — This operation is executed in various ways, but 
best with the use of a decoction of flaxseed mixed with solution 
of white soap. The flaxseed contains a mucous substance 
which dissolves in water by long boiling and in drying forms a 
lustrous mass which does not possess the hard glossy luster of 
gum. 

The glazing fluid is prepared as follows : Wash the flaxseed 
in cold water to remove adhering dust, and then boil it with 



THE DYEING OF LEATHER. 613 

four or five times the quantity of water for one hour. Filter the 
cold fluid through a closely woven cloth into an enameled ves- 
sel for the purpose of boiling with the soap. Use pure white 
grain soap free from any disagreeable odor. Convert the soap 
into thin shavings, introduce the shavings in small portions at 
a time into the boiling fluid and promote solution by vigorous 
stirring. From time to time take a sample from the vessel and 
cool it rapidly. If it forms a slippery, slightly opalescent fluid, 
the solution contains enough soap and is then again strained 
through a cloth. Add to the cold fluid a few yolks of egg, and 
beat up the whole until a uniform mass is formed. 

By adding to the boiling fluid some olive oil, at the utmost 
5 per cent, of the quantity of soap used, a glazing fluid is ob- 
tained which imparts to the leather greater flexibility than is 
obtained with the above-mentioned fluid. 

The glazing fluid is applied to the leather in a manner similar 
to the coloring matter, care being however taken to put it on 
in a very thin layer, since the thinner the layer the more beau- 
tiful the luster will be. It is best to use a large soft bath-sponge 
which after being dipped in the fluid and squeezed out, is 
passed with slight pressure over the leather. Immediately 
after drying the leather shows a beautiful luster, which may be 
still further heightened by passing the leather through between 
two rapidly revolving rolls covered with flannel. 

Tawed leather, not dyed, is glazed in the same manner as 
described above, with the exception that the glazing fluid is 
applied twice, since undyed leather absorbs more of the fluid 
than dyed leather, and hence one application would not pro- 
duce a high luster. 

In place of the above described glazing a solution of solid 
white of egg, so called patent albumin, in water with an addi- 
tion of about 5 per cent, of the weight of albumin used, of 
glycerin, may be employed. With proper concentration of this 
albumin solution, a glazing fluid is obtained which with one 
application and subsequent passing through between the 
flannel-covered rolls, imparts to the leather a high luster. 



614 THE MANUFACTURE OF LEATHER. 

Glossing. — Glossing of ordinary leather is very frequently 
effected by brushing the leather over with a rind of bacon and 
rubbing with a cotton ball covered with linen until the desired 
luster is produced. For finer qualities of leather a glossing 
mass consisting of a fat-emulsion, which also contains soap, 
may be advantageously used. Such glossing mass of excellent 
quality may be produced by boiling a good grade of white 
grain soap with five times the quantity of water until a perfectly 
clear soap paste is obtained, and adding to this soap solution, 
oil and a certain quantity of stearic acid. The effect of the 
alkali in the soap and the soda is that after continued stirring 
the oil is divided into very fine drops, and an emulsion is 
formed. By rubbing the leather with this mass it absorbs the 
oil, which renders it pliable, while an agreeable gloss is im- 
parted by the soap. A glossing mass suitable for the most 
delicate colors may be prepared according to the following 
formula : 

White grain soap 2 lbs. 

Water 5 q ts - 

Soda 14 ozs. 

Dissolved in water 21 ozs. 

Olive oil 17 ozs - 

Stearic acid 5 ozs - 

Introduce the soap solution into the soda solution and then 
add the oil and the stearic acid. Heat to from T40 to 158 F., 
and stir until the whole forms a uniform, milky mass. 

After applying the glossing mass draw the leather, colored 
side down, over a dull blade, and finally rub it with the above 
mentioned cotton ball. In place of the latter an apparatus 
may be used which consists of two wooden rolls, the lower one 
of which is covered with rubber and the upper one with cloth, 
which, however, should not be too rough. The leather, colored 
side up, is placed upon the lower roll and, while the upper roll 
revolves rapidly, allowed slowly to pass through. It must, of 
course, be held on one side, otherwise it would be carried 



THE DYEING OF LEATHER. 6l$ 

along by the rolls. By this treatment the leather acquires a 
beautiful lustre, and this operation in most dyeing establish- 
ments finishes the manipulation. 

While formerly soap-like bodies or fat-emulsions (degras) 
were exclusively used for rendering the leather pliable and for 
glossing, in modern times these substances are frequently re- 
placed by bodies obtained in the manufacture of petroleum, 
such as vaseline, or by products of the tar industry, such as 
paraffin and paraffin oil. Compared with fat-like substances 
they have the advantage of not containing free acids and not 
becoming rancid. 

In a pure state vaseline is white or yellowish, of salve-like 
consistency, liquefies by slight heating and readily penetrates 
the leather, imparting to it permanently a high degree of 
pliancy. Paraffin is at the ordinary temperature a solid crys- 
talline body of alabaster-like appearance, and melts on heating. 
There are varieties of paraffin with a melting point above 158 
F., but while excellent for the manufacture of candles, they are 
not suitable for our purpose. However, from the hardest 
varieties down there are a large number of paraffins whose 
melting points are much lower, and which are soft like warmed 
wax. Such paraffins, as well as those liquid at the ordinary 
temperature — so-called paraffin oils — are especially suitable for 
making leather pliable, and for glossing purposes. They may 
be used either by themselves or melted together with carnauba 
wax, turpentine, etc. 

GLAZING ROLLS. 

Passing the leather through between glazing rolls is a very 
suitable operation, it acquiring thereby not only a high luster, 
but also uniform thickness. The apparatus consists of two 
smooth rolls forced together by a loaded lever which presses 
uniformly upon the bearings of the upper roll. The leather to 
be glazed is placed between two polished sheets of zinc, so that 
no wrinkles are visible, and then passed slowly through be- 
tween the rolls. 



6l6 THE MANUFACTURE OF LEATHER. 

DYEING RABBIT SKINS BLACK. 

First the hair is t deadened with a so-called "green bath," 
which is composed of 9 ozs. green vitriol, 1 oz. acetate of 
copper crystals, 2*^ ozs. copper ashes and 1 quart urine. The 
skins are spread upon the table, as usual, and the hair for 4 
hours moistened with the mixture by means of a brush. The 
green looking skin is then dried and cleaned. For a very dark 
color the green bath is once or twice repeated. Then a dye is 
prepared by mixing 3^ lbs. roasted and powdered nutgalls with 
the solution of 1 ^ ozs. green vitriol in y^ pint boiling water, to 
which, after cooling, 3 quarts water is added under stirring. 
The skins are for 4 hours moistened with the dye, dried, again 
treated with a mixture of 1 pint green bath and ^ quart urine, 
dried, again brushed with equal parts of the dye *and warm 
water, kept moist for 4 hours, dried, and finally cleaned with 
bran, brushing and currying. 

Or, prepare a bath containing Z7% grains potassium bichro- 
mate and 1 5 y 2 grains cream of tartar per quart, and lay down in 
it the well- cleaned skins for 8 hours at 86° to 104 F. Then take 
up, rinse well, enter a bath containing per quart 46% grains 
Ursol (Actien Gesellschaft fuer Anilinfabrikation, Berlin) at 
86° to 104 F., turn lively at first, then lay down for three 
hours, when take up the skins, add 100 ccm. hydrogen peroxide 
per quart, re-enter, lift after 10 hours, air for 1 hour, rinse well 
and dry. If not deep enough, add 15^ grains Ursol D. and 
1 oz. hydrogen peroxide to the old bath, re-enter and proceed 
as before. 



APPENDIX. 



METHOD OF COLORING CHROME-TANNED LEATHER. 

Wm. M. Norris, of Princeton, N. J., patented August io, 1897, the 
following process or method of coloring leather. The letters patent 
are No. 588,000. Mr. Norris, in describing his improvement, says : 

" My invention consists of certain improvements in methods of color- 
ing leather, whereby I can with economy obtain more even shades of 
color than usual, and attain other advantages which are duly set forth 
hereinafter. 

"My process is especially adapted to chrome-tanned stock, upon 
which heretofore it has been difficult to produce even and satisfactory 
shades of color, owing to the nature of the tanning materials employed. 
The oxide of chromium formed in the leather when this method of tan- 
ning is practiced, does not supply an effective base or mordant for any 
of the coal-tar colors, and if, as is likely to be the case, some of the 
sulphurous acid, which is largely employed as a reducing agent in the 
manufacture of chrome-tanned leather, remains in the latter in spite of 
the thorough washing to which it is subjected, such sulphurous acid acts 
as a bleaching agent, which injuriously affects the coloring materials 
used and tends to prevent the proper coloring of the leather. 

"Heretofore in making colored leather from chrome-tanned stock 
the skins are, after being tanned and washed, put into a solution of 
some vegetable tanning matter, such as some bark or wood extract or 
gambier, and then placed in another bath containing some coal-tar 
color or anilin. I find in the working of this process that owing to the 
conditions referred to above an uneven, unsatisfactory color is often the 
result, and that the vegetable tanning agent employed causes deteriora- 
tion in the quality of the leather. These difficulties are avoided by my 
improved process, which is practiced as follows : 

" In a reel containing about six hundred and fifty gallons of water I 
dissolve three pounds of permanganate of potash, the temperature of 
the bath being about 98 Fahrenheit. Into this solution I place about 

(617) 



6lS APPENDIX. 

one thousand pounds of stock which has been thoroughly washed after 
being removed from the hyposulphite or reducing bath. At the end of 
half an hour the stock should be removed from this bath, washed to 
remove any of the permanganate which has not combined with it, 
' struck out,' and finished in the usual way. This treatment alone pro- 
duces a yellowish-brown color, which is now in demand, but if other 
colors or shades of color are desired, the stock, after being washed to 
remove the free permanganate, is placed in a solution of any suitable 
coal-tar, anilin, or other coloring matter, depending upon the color de- 
sired, and then finished in the usual way. Permanganate of potash 
destroys any sulphurous acid which may remain in the stock and is 
rapidly reduced by the skins themselves, the insoluble compound of 
manganese formed in the stock being of a yellowish-brown color and 
supplying an effective mordant for other coloring matters without 
altering or injuriously affecting the quality of the leather. 

" In order to impart to the flesh side of the skin the bluish color 
which is now generally adopted when the grain side of the skin is 
black, the skin should be first treated by the permanganate solution 
referred to above, then washed, and then placed in a drum with a very 
dilute solution of some suitable anilin, such as methyl-violet. In this 
way a good penetration of color can be secured and a good foundation- 
color for the black formed on the grain side of the skin, there being no 
injury to the skins such as follows the use of large quantities of log- 
wood and soda, which are now employed in the endeavor to secure a 
penetration of color on chrome-tanned stock. 

" Increased firmness and rigidity of the leather may be secured by 
subjecting the skins to a bath consisting of a dilute solution of ferro- 
cyanide of potassium (yellow prussiate of potash), say about five 
pounds of the ferrocyanide to six hundred and fifty gallons of water, 
preparatory to treatment with the bath of permanganate of potash, as 
described above. 

" In working my process I have found that the best results are ob- 
tained by using the proportions specified, but I do not confine myself 
to these proportions, although in using such an article as permanganate 
of potash, which is a powerful oxidizing agent, dilute solutions only 
should be employed." 

ART OF TAWING HIDES OR SKINS. 

The specification for Wm. M. Norris' patent No. 588,874, dated Aug. 
24, 1897, is as follows : 



APPENDIX. 619 

The invention relates particularly to that method of tawing leather 
now being largely practiced and known as "chrome" tanning, and the 
object of the invention is to attain greater economy and other advant- 
ages, hereinafter particularly pointed out, in the practice of said method. 

The "beam-work" of my improved process is substantially the same 
as the beam-work in chrome tannage as at present ordinarily practiced, 
and the tanning is substantially the same, with the exception that in my 
improved process I provide for a continuous evolution of nascent hydro- 
gen in the second or reducing bath. This nascent hydrogen operates to 
change the thiosulphuric acid or the sulphurous acid present or liber- 
ated in said bath into hyposulphurous acid, which is a more powerful 
reducing agent and possesses other advantages, hereinafter referred to. 

By the term "hyposulphurous acid" as used in this description I 
mean not the compound which has been some time so called, and which 
is otherwise and more properly known as "thiosulphuric acid," but the 
compound expressed by the symbol 1 H. z S0 7 or H 2 S,0 4 , and known also 
as " hydrosulphurous acid." 

I first tan or taw the hides or skins by subjecting them, as heretofore 
practiced, to bichromate of potash or analogous salt, such as bichromate 
of soda, dissolved in water, to which an acid, such as hydrochloric acid, 
is added, taking, say, for each one hundred pounds of raw hides or skins 
about five pounds of bichromate of potash or its equivalent and two and 
one-half pounds of hydrochloric acid of 21 Baume or an equivalent 
amount of sulphuric acid, the amount of water in the bath being suffi- 
cient to properly cover the skins. The hides or skins having been left 
in this bath until thoroughly impregnated with the chromium compound 
are then removed, pressed or " struck out " to remove surplus liquor, 
when the stock is ready for the reducing bath. 

So far my improved process does not depart from the process of 
chrome tanning as now ordinarily practiced, but in the present practice 
of chrome tanning, as known to me, the second or reducing bath con- 
sists, ordinarily, of hyposulphite of soda, by which I mean the compound 
Na 2 S 2 3 , more correctly designated as " sodium thiosulphate," and hy- 
drochloric acid in water. The thiosulphuric acid liberated by the 
action of the hydrochloric acid upon the hyposulphite of soda in this 
ordinary reducing bath is veiy unstable, and is resolved almost as rapidly 
as generated into sulphurous acid and sulphur, this action being so 
quick and energetic as to be easily observable. The active agent, 
therefore, in this bath is sulphurous acid, with which the hides or skins 



620 APPENDIX. 

become impregnated, while sulphur is thickly deposited in the fibres on 
the grain and flesh sides of the hides or skins. To free the latter from 
the sulphurous acid and sulphur requires a thorough washing, which 
usually takes considerable time and requires the use of a number of reels 
or other apparatus, which might be otherwise more advantageously 
utilized, consumes, furthermore, much water, and is sometimes injurious 
to the leather. To overcome these objections to the now commonly 
employed reducing bath, I add to said bath metallic zinc, whereby 
there is continuously liberated in the bath nascent hydrogen, which 
operates to convert sulphurous acid, when formed, into hyposulphurous 
acid, the reaction being expressed by the equation 

2H 2 S0 3 +H 2 =H 2 SA+2H 2 0, 

or, as it is stated in other books on chemistry, 

H 2 S0 3 +H 2 =H 2 S0 2 +H 2 0, 

and, doubtless, it operates also to lessen or prevent the formation of 
sulphurous acid by converting the thiosulphuric acid produced by the 
action of the hydrochloric acid upon the hyposulphite of soda directly 
into hyposulphurous acid. 

The method which I prefer for the development or liberation of the 
nascent hydrogen is the very simple and economical method of placing 
a number of pieces of metallic zinc in the vessel containing the bath, 
these pieces being, where a reel is employed, sufficiently large and 
heavy to remain at the bottom of the bath without being disturbed by 
the motions of the liquor caused by the paddles in the reel. The bath 
being acid, a continuous liberation of nascent hydrogen from the me- 
tallic zinc will take place, but I wish it understood that I do not confine 
myself to this particular method of evolving nascent hydrogen in the 
bath, as other modes may be employed. 

I have found the following to be an efficient reducing bath made in 
accordance with my invention, although it will be understood that the 
proportions specified may be departed from without departing from the 
invention. For the treatment of, say, one thousand pounds of skins, a 
bath of 125 pounds of hyposulphite of soda and 50 pounds of muriatic 
acid in 650 gallons of water is prepared, and to this bath is added 60 
pounds of metallic zinc. The zinc should be allowed to remain when 
the liquor is drawn off after the bath is exhausted and a new bath is 
prepared, and about 5 pounds of metallic zinc should be added about 
once a week. 



APPENDIX. 62 1 

Instead of having pieces of zinc at the bottom of the reel, the latter 
may be lined with sheet zinc, thus exposing a large surface to the action 
of the acid solution. 

Some manufacturers for their reducing or second bath use instead of 
hyposulphite of soda and acid, a solution of what is commercially 
known as "bisulphite of soda," prepared for this purpose. This I 
understand to be an aqueous solution of sulphite of soda saturated with 
sulphurous acid gas, and the bath may be the same as before given, 
except that the acid is omitted and the hyposulphite of soda is replaced 
by an equal number of pounds of the bisulphite solution. In this case 
the zinc is used in substantially the same way as formerly described in 
connection with the reducing bath of hyposulphite of soda and muriatic 
acid. Although no sulphur is developed in such a solution, the libera- 
tion of nascent hydrogen in such a bath would convert the sulphurous 
acid into hyposulphurous acid, which would be an advantage, and much 
less bisulphite would be required. Hence, my invention is applicable 
to a bath of this character, and is so claimed. 

Nascent hydrogen acting upon a solution of bisulphite of soda gives 
rise to the reactions which are expressed by these equations : 

4NaHS0 3 +H 2 =H 2 S 2 4 i- 2Na 2S03+2H 2 0, 
or 

2NaHS0 8 +H 2 =H 2 S0 2 f Na 2 S0 3 +H 2 0. 

It is customary after skins are taken from the first or chrome bath 
and struck out to dip them each singly into a dilute solution of hypo- 
sulphite of soda, to which muriatic acid is added, this treatment being 
for the purpose of bringing the stock into the best condition for the 
reducing bath, and for effecting a slight surface reduction, which acts 
to prevent the washing out of the chromium compound from the 
stock when placed in the reducing bath. 

A zinc-lined vessel may be advantageously used to contain the solu- 
tion into which the stock is thus dipped, or pieces of zinc may be 
added to the solution, as the nascent hydrogen which will thus be de- 
veloped will increase the efficacy of the solution, less hyposulphite of 
soda will be required, and less sulphur will be developed. 

The results of my improvement are : 

First. A comparatively small amount of sulphur is liberated and little 
or no sulphurous acid brought into contact with the skins or hides, so 
that when the latter are taken from the reducing bath very little wash- 



622 APPENDIX. 

ing is necessary to perfectly cleanse them and make them quite neutral 
and in good condition for the subsequent finishing operations, and in 
this way material economies of time, labor and apparatus are gained. 

Second. Hyposulphurous acid being a much more powerful reducing 
agent than sulphurous acid, the quantity of hyposulphite of soda requi- 
site for the reducing bath is by my improvement materially reduced. 
About one-half of the quantity of hyposulphite of soda heretofore con- 
sidered necessary will in my improved process suffice — that is to say, 
where 20 per cent, of the weight of the skins of hyposulphite of soda 
and 5 per cent, of the weight of the skins of muriatic acid have been 
used heretofore, 10 per cent, of hyposulphite of soda and 5 per cent, 
of muriatic acid will be sufficient when my improved process is 
employed. 

BORAX. 

Tanners and curriers fully realize that soft water is a great aid in 
making good leather. Some of the most beautiful leather in the world 
comes from Denmark. In that country spring water is a great rarity, 
and the many small streams and lakes are fed mainly by rain water ; the 
water is very soft, and particularly well adapted for the production from 
raw material treated with it of a pliable leather of most excellent feel. 

The waters of the United States vary greatly in their hardness, and 
many a tanner has failed in business because there was a leak in his 
tannery which he could never find, search as he would, and this leak 
was constant in its working, never ceasing, eating his profits away, eat- 
ing up his hides and skins, eating up his bark pile, eating up his dye 
stuffs, and in the end ruining him beyond repair. This leak worked in 
the day time, in the twilight, in the night, on Sundays and on all other 
holidays, constantly the same. This leak was hard water. 

There is no necessity for any tanner, or currier, or leather dyer to 
work with hard water, as one of the best water softeners in the world is 
now within his reach at a low cost. We refer to borax, which can now 
be bought for about 5^c. per lb. ; and 5 lbs. of borax will soften 1,000 
gallons of water and render it fit for the soaks, the leaches, or the dye 
house. It is best to first dissolve it in boiling water and then add the 
water to be used under constant stirring. 

Borax is also one of the best known agents for whitening or bleach- 
ing leather of all kinds. Every known variety of russet leather is 
bleached with borax and sulphuric acid. After this variety of leather 
is shaved, it is put into a pin-wheel with a solution of borax, 2 pounds 



APPENDIX. 623 

to 100 gallons of water, and washed thoroughly. While it is still in the 
wheel, it receives a bath of weak sulphuric acid to neutralize the alkali, 
and, at the same time, take out any iron stains that may be in the 
leather. The borax bath is drawn off before the sulphuric acid bath is 
applied. The borax bath works out the dirt and makes the leather 
appear much darker. The sulphuric acid bath changes the color of the 
leather to a much lighter shade than it was originally. 

This is one of the secrets of the chrome process of tanning kid. 
Some manufacturers make their kid of a nice white color, and all of the 
other manufacturers are wondering how they do it. The above process 
of bleaching or whitening the leather with borax and sulphuric acid 
explains it. In kid some makers after the sulphuric acid bath is drawn 
off, give the leather a hot bath of Sicily sumac and alum, which imparts 
a still lighter shade, and at the same time softens it. The kid is then 
rinsed in clear water in a tank, and is immediately struck out to remove 
the water and surplus sumac. The leather is now ready to be dyed or 
colored. Then, again, the working of the dirt out of the hide or skin 
by the aid of borax before placing it in the tanning liquor, be the liquor 
vegetable or mineral, is a great help to rapid tannage, as it is well 
known that the cleaner a hide or skin is, when it is placed in the liquor, 
the quicker it can be tanned. Borax is one of the gentlest of the alka- 
lies ; but it is the mortal foe of dirt. It utterly destroys it, and that is 
the secret why all the laundries in the country use borax to soften the 
water in which they soak or wash the clothes to be laundered. 

Borax is also one of the greatest preservatives known. All the larger 
packers of the country are using it to preserve their meats, and it is also 
being used as a preservative for hides and skins in the place of salt. It 
leaves no salt stains, and hides or skins preserved with borax are there- 
fore worth more than those preserved with salt. 

In the making of " sig" stains, blacks and pastes for leather, borax 
is the currier's friend ; if the water is hard it is not good for these pur- 
poses, but a little borax softens the water and makes it fit for use. The 
same is true of the finishes. No other agent will cut the shellac used 
and soften the water so well as borax. It is also one of the best known 
agents in the preparation of blood and egg albumen, and is equally 
good in the preparation and preservation of egg yolk, so much used by 
makers of kid and glove leather. 

Borax has been used in the leather industry for more than fifty years, 
each year extending its use, until now no tanner, currier or leather dyer 



624 APPENDIX. 

can afford to be without it. He must keep it on hand the same as he 
does his bark or his hides or skins, in large or small quantities, accord- 
ing to his uses for it, and they are many about a tannery or currying 
shop. 

One reason of the growing use of borax is its steady fall in price dur- 
ing the past fifty years from 76 cents a pound in 1847 to 5^ cents a 
pound in 1897, one-fifteenth of its cost fifty years ago. 

The following table shows the range of the average New York whole- 
sale price of borax during the past fifty years : 

Cts. Cts. Cts. 

1847 per lb.. 76 1864 per lb.- 39 1881 per lb.. 13% 

1848 72 1865 37% 1882 13% 

1849 70 1866 33 1883 14% 

1850 68% 1867 35% 1884 9% 

1851 67^ 1868 33^ 1885 814 

1852 66 1869 35 1886 b% 

1853 65 1870 30% 1887 5% 

1854 64% 1871 3114 1888 7 

1855 60% 1872 32 1889 7% 

1856 57 1873 2 4 | 1890 7% 

1857 56K 1874 I4i 1891 1% 

1858 54 1875 12% 1892 7% 

1859 5° 1876 10% 1893 7% 

i860 48 1877 9% 1894 7 

1861 45 1878 8% 1895 6 >2 

1862 42 1879 9 1896 5% 

1863 40 1880 1214 1897 S% 

Borax, in addition to its many other uses in the currying shop, is also 
employed for cutting the oils and fats used in stuffing leather, it having 
displaced sal soda, chip soap, soapine and all other alkalies for this pur- 
pose. Borax is also used in the best known mordants for colored leathers. 
It " bites" or mordants the hides or skins uniformly, and is not harsh 
in its action, because it is so gentle an alkali. This is the chief cause of 
its popularity with the leather dyer. This gentleness makes its value in 
the kid industry to neutralize the excess of fat liquor and to wash all 
leather tanned by the chrome process, this washing giving a more uni- 
form color and lustre to the skins after coloring or dyeing. A recent 
writer has truly said that it is not easy to convince any old tradesman 
that a better mode can be found than the one he has practiced all his 
life and all his ancestors before him. Some tanners have quoted the 
maxim, "leave well enough alone," adding, "we have done so well by 



APPENDIX. 625 

the old mode, we shall not make any change." But you will have to 
make a change. Modern business is done on a different plane from the 
business of the past. It is now truly a fight, a battle in fact — the 
fighting is done with the brain — and the man who survives is the one 
who watches to see if any economy can be practiced or any saving be 
made in any of the departments of his tannery or currying shop. 

A most important use of borax in the tanning trade is its employ- 
ment in softening the water for its soaks, cleansing and preserving the 
hides and skins and preventing the withdrawing of their gelatine, thus 
making heavier, more solid and more salable leather. 

There are two reasons why the tanners of all kinds of hides and skins 
should use it in their soaks, as the soaks are always kept fresh and pre- 
vented from becoming putrid or foul, and thus withdrawing valuable 
gelatine from the hide or skin under treatment. Borax can be used 
not only in the soaks, but in the limes and bates as well. Its antiseptic 
qualities keep all of these liquors fresh and sweet. It renders water 
beautifully clear, sweet and soft, and just in the right condition for the 
soaks, just right for the leaches, for scouring and for the final cleansing of 
the hide or skin preparatory to placing it in the tanning liquor. Borax 
removes all taint, dry rot or decomposition from the hide or skin, and 
all other unhealthy changes, and produces a leather which will repay 
the tanner or currier ten times over for its use. It kills the bacilli of 
anthrax when used in the soaks, as it thoroughly disinfects the hide or 
skin, which is exposed to its action. We will speak of anthrax later on. 
Borax can be used in all climates and in all waters, hard, soft or sea 
water, and will instantly destroy all unhealthy and infectious germs 
wherever located, and in whatever part of the hide, skin or tanning ma- 
terial they may be. It will remove all dirt quickly, as it is one of the 
most perfect of cleansers, and will prepare the hide or skin for the 
reception of the tanning liquor more thoroughly than any other agent. 
In the rinsing or cleansing of the hide or skin preparatory to placing it 
in the tanning liquor, borax will be found to be the cheapest, most 
harmless and most efficient of the cleansing agents. In the leaches, 
borax will be found to be a very efficient agent for softening the water, 
as hard water has to have its hardness overcome by the tannic acid in 
the bark before it can become efficient for leaching the bark. Caustic, 
soda and similar chemicals may be used for softening water ; they are 
cheaper than borax, but will not do the work so efficiently, as they all 
withdraw the gelatine from the skin or hide, and thus make a soft and 
40 



626 APPENDIX. 

less salable leather. Borax is, therefore, a cheap agent. The antisep- 
tic qualities of borax preserve the liquors and keep them fresh and 
sweet, and at the same time, it being an alkali, very gentle fermenta- 
tion of the bark is caused, so as fully to extract the tannin and to allow 
it to enter into combination with the hide or skin without becoming 
crystallized. It is this fact which makes borax so valuable for soften- 
ing water for leaching tan bark. Borax is the material which is de- 
pended upon in nearly all the so-called quick tanning processes to do 
the work in aiding the penetration of the tannin. It improves and at the 
same time cheapens all leather produced. Leather is made in the beam 
house — not in the tanyard. If you lose the gelatine in the soaks, limes 
or bates it can never afterward be replaced in the hide or skin, and the 
result of tanning will only be an inferior leather. Borax stands alone 
in its antiseptic, decay-arresting, purifying attributes. Tanning belongs 
to those industries in which the decomposition of organic materials by 
micro-organisms plays an important role. The following recognized 
putrefactive ferments have been met with in tan liquors : Bacillus fluor- 
escens liquefaciens (Flugge) ; B. megatherium (De Bary) ; B. subtilis 
(Ehrenberg) ; potato bacillus; B. mesentericus fuscus (Flugge) ; B. 
mycoides (Flugge) ; B. viscosis (Frankland) ; gas-forming bacillus 
(Eisenberg) ; white bacillus (Maschek) ; proteus vulgaris, proteus mira- 
bilis (Hauser) ; Bacillus butyricus (Hueppe) ; white streptococcus 
(Maschek) ; worm-shaped streptococcus (Maschek) ; chey coccus 
(Maschek) . Besides these known species there are other yet unde- 
scribed, but putrefactive organisms, most of which have a similar effect 
on the subsequent fermentation. They naturally occur most numer- 
ously in the weak liquor. As an example of the way certain bacteria 
get into a tannery, the following is given : The waste water of a large 
works discharged into a neighboring river was found to contain large 
numbers of proteus vulgaris and B. fluorescens liquefaciens ; the same 
bacteria were found not only in the water, but in the limes and tan 
liquors of a tannery a mile down stream, drawing its waters from the* 
same river. Where the cold-sweat process of unhairing is used a still 
larger number of putrefactive organisms are found in the liquors. 
Oak-wood and quebracho extracts, which ferment with difficulty, owing 
to a lack of suitable nutrient material, are good growing ground for 
molds. Their special function is the decomposition of tannins of a 
glucoside character. It will be seen from the above mentioned organ- 
isms that the souring of the tan liquors is influenced by numerous fac- 



APPENDIX. 627 

tors, and is no regular fermentation, such as alcoholic or acetic acid 
fermentation. A bacteriological examination of the liquors has shown 
a whole series of bacteria and fungi in the liquors, but chemical analysis 
shows the following to be the chief products : Carbonic acids, ethyl 
alcohol, acetic acid and lactic acid. Although all these are of equal 
theoretical importance, only the two latter are to be considered, and the 
bacteriological research is much simplified by considering only those 
species which produce these two acids. Of the two, lactic swells the 
skin better than acetic acid. The chemist who made this examination 
in Germany found no organism in tan liquors capable of fermenting glu- 
cose direct to acetic acid, and he considers that the production of this 
acid in the liquors is the result of two distinct processes : (1) the for- 
mation of alcohol ; (2) the oxidation of the alcohol to acetic acid ; that 
lactic and acetic acids are the result of entirely different chemical pro- 
cesses, and are produced by different organisms. The present genera- 
tion need fear no scarcity of hemlock or oak bark. The question of 
the day in the struggle for economical results in the tanning industry is 
leaching. Many tanners delude themselves with the idea that they are 
getting the best results possible considering the conditions under which 
they are working, and by an occasional analysis of their spent tan they 
apparently prove their position. The results to be obtained it must be 
admitted consist in the extraction of a maximum amount of tannin with 
a minimum amount of water. If the water is hard it will take more of it 
to do the leaching than if it is soft. Borax softens the water and allows 
it to take immediate hold of the tan bark. What we must seek to do in 
leaching is to pass the water through the bark and not around it. Water 
which has been softened with borax is more penetrating, when either 
hot or cold, than is water which has not been softened. In this coun- 
try, in the leaching of oak bark, hemlock bark, canaigre and other tan- 
nins, hot water is generally ^employed. The temperature at which it 
goes on the head-leach is not material ; anywhere from ioo° to 140 F. 
will do, but its temperature should be gradually increased until the water 
is at the boiling point on the tail-leach. Only in this way can the max- 
imum amount of tannin be obtained. The antiseptic qualities of borax 
preserve the bark liquors and keep them fresh. The word antiseptic is 
derived from anti (against), septikos (putrescency). As an antiseptic, 
borax stands pre-eminent, and may therefore well take the place of car- 
bolic acid, vitriol, chloride of lime, creosote and arsenic, wherever em- 
ployed. We do not care whether you depilate with lime, sulphide of 



628 APPENDIX. 

sodium or any other agent, either sole, belting, harness or upper leather 
of any kind, whether it is produced from hides or skins, it is necessary 
that the hide or skin should be clean before it is placed in the tan 
liquor. Sour liquor will not then be required to overcome the depilitant. 
Then feed the hide or skin regularly ; do not check it with too much 
liquor or too strong a liquor, or starve it by withholding supplies. Re- 
member that there is no vacuum of time when the hide or skin is not 
feeding. If it is not fed continuously it will exude and lose its gela- 
tinous matter, and this matter, once lost, can never be recovered or re- 
placed. Borax is the only substance which will properly prepare the 
hide or skin for the reception of the tannin liquor. Then, too, borax is 
one of the best agents for softening water to be used on hides and skins 
preparatory to stuffing. To obtain a fine grain color the leather must 
be moistened, and must contain a certain amount of water when the oil 
or fat is put on, so as to resist the penetrating properties of the oil or 
fat, which can only be absorbed as the water is slowly evaporated. Do 
not make the mistake of greasing the hide or skin on both sides ; this 
will prevent the evaporation of the water and the penetration ot the oil 
or fat. Water which has been softened with borax has just a trace of 
this alkali in it, but enough to assist the penetration of the oil or fat. 
This applies to both hand and drum stuffing. In dyeing leather, the 
use of soft, bright, clear water permits of the getting of good colors, 
particularly when there are bright shades. In fact, where any alkali is 
now employed in the tannery or currying shop, it will be found that 
borax will take its place and will give more satisfactory results and 
better leather. The harness leather men and fancy leather manu- 
facturers, and, in fact, all makers of leather, are already using borax 
extensively, and now it is so cheap as to be within the reach of all 
leather producers. For grain, split, buffed, patent, enamel, furniture, 
in fact, any leather which requires a smooth split, there is no agent 
as good as borax, to be used in dampening before splitting. The use 
of boracic acid as a [bate for chrome tanned has been explained on 
page 335, and hence needs no special description here. Borax is 
largely .used in the process of chrome tannage for washing the hides and 
skins after they come from the chrome liquor. They should then be 
well washed in warm water, then in i to i}i per cent, of borax solu- 
tion, and finally again in water. They are then ready to be fat liquored, 
stained, colored, set out, oiled off, etc., and finished. 



APPENDIX. 629 



Acting upon the request of the Secretary of Agriculture, the Treasury 
Department has requested the Secretary of State to instruct all consular 
officers of the United States to refuse authentication of invoices of 
hides of meat cattle from districts in which anthrax exists. This re- 
quest is made in view of the fact that a number of deaths of human 
beings and cattle recently occurred at Falls Creek, Pa., in consequence 
of the manipulation of hides in tanneries at that place. 

Much apprehension has been awakened in the United States during 
the past few years by the supposed appearance of anthrax. Anthrax 
in its most malignant form exists in the countries of southern Europe 
and the Orient. Cattle, sheep, goats, and once in a while the horse, are 
attacked by the disease, which manifests itself as a splenic fever in 
those animals. 

Unfortunately, the disease is easily conveyed to man in any climate, 
but only through inoculation. The medium through which man may 
be afflicted is the hair, wool or hides of any animal which has died of 
the disease. If a man's hand should have an abrasion and he should 
be among infected hides, the specific bacillus of anthrax may inoculate 
him where the abrasion is. In man its manifestation is variously de- 
scribed as malignant pustule, contagious carbuncle, wool sorters' and 
hair combers' disease. 

It is therefore known in the human subject as a "wound disease." 
Unless the treatment is speedy the inoculation is rapidly followed by a 
virulent form of local inflammation, attended with sloughing and speedy 
systematic poisoning. The dust of infected wool or hair invades the 
throat and windpipe in wool sorters' disease, causing inflammation, 
poisoning all the surrounding tissues, and ending life by most distress- 
ing symptoms. After the inoculation there is great prostration, and 
death follows in a day or two from exhaustion. 

Naturally, health boards of seaport cities are anxious to have a 
thorough inspection of all hides, wool and hair imported. There are 
very rare instances of anthrax in New York City, but it will be found on 
the records of the hospitals that there are perhaps a half dozen cases 
every year. 

The New York City health authorities have been on their guard, and 
there is a constant inspection of incoming hides, hair and wool. 
President Wilson, of the Health Board, says that there is no ground for 
fear of anthrax because of its supposed appearance in other parts of 



630 APPENDIX. 

the country. On the subject of anthrax Dr. H. M. Biggs, the chief 
bacteriologist of New York city, says : 

"In the human subject the disease is not necessarily fatal. If there 
is a rapid treatment after inoculation the patient generally recovers. 
The treatment is excision or the cutting out of the diseased flesh. 
There are few cases, and the element of danger is extremely small. 

"There are no marked external indications of the disease in cattle. 
Once started, it may go through whole pastures." 

Among the earliest of Pasteur's works was the preparation of an an- 
thrax vaccine to prevent the spread of the disease in animals. The 
vaccination has resulted in an inestimable amount of benefit, and the 
human race has been saved from a serious danger. It is one of the 
monuments to the name of Pasteur. 

The disease in cattle may originate in the food. The bacillus is most 
persistent. There is no time limit to its existence in hides, hair and 
wool. It will offer danger for years. 

The spores of the bacilli are used as tests for disinfectants, and, as has 
been previously stated, borax, when used as a preservative for the hides 
and skins, or in the soaks, will kill them. 

DEGRAS. 

Degras, the kind made from wool washing, not the French degras, is 
used in finishing three-quarters of the American finished upper leather, 
of which nearly $9,000,000 worth was exported from the United States 
in 1896. This export business is rapidly increasing. Degras imparts 
peculiar qualities to the leather that no other greases and no oils can 
give ; in fact, after the hide and bark, it is the principal article used in 
the manufacture of upper leather. Some tanners have tried to substi- 
tute menhaden oil for degras, but with only poor results. 

The manufacturer of good upper leather can not afford to use men- 
haden oil at any price, as it contains a gummy substance that is likely 
to fry out when the leather has been finished a short time. This in ex- 
port leather would be fatal. In the old days, when " anything was good 
enough for leather," menhaden oil was used, but with only disastrous 
effects, as the oil became gummy, and, when the leather was rolled up 
for a little while, the rolls could not be opened because the sides were 
so stuck together by this gum or fish glue. The leather manufacturer 
who would go back to menhaden oil would ignore the improvements 
which have been made in his craft during the past twenty-five years. 



APPENDIX. 63 1 

The Japan fish oil, which is being used to some extent, we are in- 
formed, is not like cod oil made from livers, but is similar to menhaden 
oil, a product of pressing the whole fish ; and hence, when it is used 
for leather, the leather will gum or stick together when rolled similar to 
menhaden oil, the only difference being that the Japan fish oil takes a 
little longer time to stick the leather together, probably from having 
less fish-glue in it. 

AMERICAN DEGRAS FROM WOOL WASTE. 

Real degras is the oxidized fish oil wrung from chamois skins during 
the process of tannage, and it is imported from France. An imitation 
degras is made from wool waste, and is very largely imported from Eng- 
land and Germany. 

The United States manufactures degras from wool waste in small 
quantities, but is about to embark in its production on a larger scale, 
and, strange to say, it is driven to do this because of the low price of 
wool. 

The opponents of a tariff on wool assert that the great decline in the 
market price of wool is owing not to tariff legislation, but to the fact 
that the wool product of the world has doubled since 1870, and is also 
owing to the large utilization of cheap substitutes for wool. 

An influence that may become a more potent factor in the near future, 
in increasing the availability of the present supply of wool, and thereby 
diminish the cost, is the promised solution of the vexed problem of the 
saving and utilization of the enormous wastes in the process of manu- 
facturing. Recently it has been boldly asserted, and almost clearly 
demonstrated to a committee of wool manufacturers in Providence, that 
it is possible to utilize the by-products that now go to waste, so as 
to make them an important source of revenue to the manufacturer. At 
the same time, by this new process of cleaning, called the solvent pro- 
cess, the value of the fibre would be enhanced fully one cent a pound. 

It is asserted that the amount of refuse material daily turned into the 
river by the wool manufacturers in the Olneyville, R. I., district is 
6,000,000 gallons, in which are about 50,000 lbs. of grease ; and besides 
a large quantity of logwood, acids and other substances, far in excess 
of what is generally supposed. The consumption of raw wool in this 
manufacturing district alone is estimated at 20,000,000 to 25,000,000 
pounds per annum, and the committee stated that there was a loss of 
about 50 per cent, during the washing process. 



632 APPENDIX. 

According to statistics, there is a shrinkage of from 58 to 60 per cent, 
on some 500,000,000 pounds of wool annually consumed in the United 
States. 

The startling announcement was made that the manufacturers were 
throwing away more money on the by-product than is produced by the 
wool product. 

The man who made this statement gave, as an illustration, that they 
were putting into their streams 2,500,000 pounds of bicarbonate of 
potash and losing $250,000 annually. He also showed that in 25,000,- 
000 pounds of wool there is 20 per cent, of wool fat, and therefore 
5,000,000 pounds of degras is thus thrown away. There are now 
11,000,000 pounds of degras imported into this country annually from 
Europe, and for every 5,000,000 pounds of wool consumed, $10,000 a 
year is paid for wool oil to put back into the wool. 

The process proposed by Mr. N. Burton McDowell, of New York City, 
is effected by the introduction of a certain kind of oil in the cleansing 
pots. This oil is made by the Standard Oil Company, and can be used 
over and over again. A plant is now being erected to treat 16,000,000 
pounds in Lawrence, Mass. The cost of the process, so far as the 
cleaning goes, is nil, or so nearly so that it counts for nothing. In ad- 
dition, the cloth scourings are taken and treated for the indigo they con- 
tain. Mr. McDowell has offered to put in a proposition, accompanied 
by a bond, to take the wastes and treat them in the manner proposed, 
which the committee voted would be satisfactory. 

This process, if successfully adopted, may work a revolution in the 
manufacturing of woolen fabrics, decreasing the cost of the raw material 
by enhancing its value, thereby giving a larger margin of profit to the 
mill owner while decreasing the cost of the manufactured product. 

It would seem from the above statement that we have the greasy 
wools in this country, from which to make a degras equal to that which 
we now import from England and Germany. 

THE PER CENT. OF WATER IN DEGRAS. 

To determine the proportion of water in degras, says a correspondent 
of La Halle aux Cuirs, there are two methods in general use. The 
first consists of heating a previously determined weight of the degras in 
a clay crucible by means of a stove or a sand bath, and calculating the 
amount of water by the loss in weight. The temperature in this opera- 
tion ought to be maintained at 221 F. If it rises to 239 or 247 F., 



APPENDIX. 633 

it gives out whitish vapors of a pronounced odor, which evidently con- 
sist of something beside steam. Thus the chief objection to this 
method — that it gives results which are often too high — is not without 
foundation. If the operator does not have convenient access to a ther- 
mostat, or heating apparatus, which, automatically maintains the tem- 
perature desired, it requires constant watchfulness and considerable loss 
of time. 

The second method consists of agitating a given amount of degras in 
a graduated tube, with benzine, and leaving it until the water has sep- 
arated itself, when the per cent, may be calculated by the graduations 
of the tube. The value of the results obtained by this process is also 
open to discussion. The water being separated, in a state of emulsion, 
it is impossible to exactly determine its actual volume. Owing to the 
different density of water and of fatty substance, the figures obtained 
will not coincide with those by the first method, and they are also influ- 
enced by the temperature maintained. In view of the many possibili- 
ties of error, it may be considered a happy chance if the result approxi- 
mates the real amount sought to determine. In fact, by either system, 
different analyses of the same degras often present considerable var- 
iation. 

Thanks to a very simple artifice, however, it is an easy matter to sep- 
arate at the temperature of boiling water all the water which the degras 
contains. This may be accomplished by pouring upon the latter from 
time to time small quantities of concentrated alcohol, which evaporates 
the moisture from the warm liquid. A platinum capsule should be used 
to heat a few grammes of degras to the boiling point and a few cubic 
centimeters of alcohol used. When the last addition of alcohol is evap- 
orated, the crucible is allowed to cool and the contents weighed ; then 
the operation may be repeated to make sure that no further shrinkage 
can be obtained. 

This process does not require continual watchfulness, it takes less 
time and excludes any risk of overheating. The writer adds that he 
has already employed it for some months, and it has always given 
constant results. The idea is not absolutely new, as it has been em- 
ployed in pharmacy for separating oleate of lead from its moisture. 

TANNING MA1TERS. 

Our methods of determination of tanning matters are far from per- 
fect, and, as Dr. W. Schmitz-Dumont truly says in Der Ledermarkt : 



634 APPENDIX. 

The accuracy of the results obtained in the analysis of tanning ma- 
terials depends upon the quality of the hide-powder used. It is a 
matter of great difficulty to make or to obtain a hide-powder of uni- 
formly good quality. In spite of the greatest caution observed in 
making the powder, the best hides often produce powders which are 
worthless, simply because they are not sufficiently insoluble in water or 
because their structure is too horny and gelatinous. The heating of the 
mill-stones during the grinding of the hide or the change in structure 
during the drying of the powder will account for the uncertain results. 
It is therefore desirable to obtain a substitute for hide powder, combin- 
ing the following properties : 

i. Absorption of tannic acid in the same manner as hide powder. 

2. Insolubility in water. 

3. It must be easily manufactured. 

Experiments were first tried to separate tannin from solution by 
means of gelatin, hardened with alum and with chromic acid, but with- 
out success. The most satisfactory results were obtained with " forma- 
lin-gelatins." This is a commercial article, used as an antiseptic. It 
is a coarse, sandy powder, and absorbs tannin quantitatively and 
quickly, especially when the solution is heated to 104 F. But owing 
to the high price of the commercial article, and to its being con- 
taminated with trioxymethylene (which has to be removed by long ex- 
traction with hot water, in order to prevent errors in the results), it 
seemed desirable to make this preparation in the laboratory. The fol- 
lowing method was employed for making the "formalin-gelatin :" 

Thick, woolly filter paper, free from soluble matter, is thoroughly im- 
pregnated with a hot 10 per cent, solution of gelatin, and placed hori- 
zontally on glass rods to dry in the air; it is then left for twenty-four 
hours in a 2 per cent, solution of formalin, and dried at 203 F. 
The sheets of paper now show a horny appearance, resembling cellu- 
loid ; they are cut into strips and ground in a mill (a coffee mill will 
do). A woolly powder results, resembling hide powder in appearance. 

This powder is again treated for twenty-four hours with a 2 per cent, 
formalin solution ; the solution is' then pressed out and the powder 
dried at 212 F., until the loss of weight is only 0.1 per cent, in 
thirty minutes' drying. The preparation must now be treated with 
hot water in a suitable extraction apparatus in order to remove the tri- 
oxymethylene ; the extraction must be continued until too cubic cen- 
timeters of the extract give no reaction for formaldehyde with alkaline 



APPENDIX. 635 

resorcin solution. The water is then pressed out and the powder dried 
on the water-bath until it feels dry. Thirty grams of the preparation 
were treated with 400 cubic centimeters of water for twenty-four 
hours, with occasional shaking, in order to test it. 300 cubic centi- 
meters of the clear filtered liquor on evaporation left a residue weigh- 
ing 0.0023, an inconsiderable amount in a tannic acid determination. 

A number of parallel determinations of tannic acid were made to 
compare the action of the gelatine compound with hide-powder. 
Twenty grams pine bark were extracted with one liter of water ; 200 Cc. 
were shaken with each of the two absorbents. The manipulation with 
hide powder was according to the usual method. 200 Cc. of the extract 
solution were shaken for one hour with ten grams of the gelatine com- 
pound. The absorption proceeded more rapidly if the solution was 
warmed to 95 or 104 F. ; in twenty minutes the solution was al- 
most colorless, and gave only a faint reaction with ferric chloride. 
The solution was then filtered and left for twenty-four hours with ten 
grams of the gelatine preparation; filtered and dried to constant 
weight at 212° F. 

The following amounts of non-tannins were obtained per 100 Cc. 
extract : 

Hide. 
Pine I o. 1 599 

0.1576 
Pine II 0.1630 

Oakbark I 0.1895 

" o. 1 870 

Oakbark II 0.1280 





Gelatine 


Gelatine. 


(heated) 


0.1582 


0.1589 


0.1587 


0.1580 


0. 1 605 


0.1621 




0.1613 


0.1879 


0.1888 


0.1269 


0.1280 


0.1277 





In evaporating the solutions of non- tannins, 5 grams of ignited 
quartz sand were added. 

The results obtained were most favorable for the "formalin-gelatin •" 
but unfortunately a second preparation of it did not give as good results. 
The first preparation weighed only 300 grams ; the second preparation 
amounted to two kilograms. Thirty grams of the new preparation, 
when treated for twenty-four hours with 400 Cc. water, gave 0.0063 
grams residue per 100 Cc. A further treatment with water brought the 
weight of residue to 0.0102 grams per 10 Cc. It seems probable that 
in manipulating the larger quantity of material, the preparation was not 



636 APPENDIX. 

sufficiently dried to change the gelatine completely to the insoluble 
form. Or perhaps too long continued washing with water caused the 
compound to revert to the soluble form. Better methods of making 
the preparation will probably be suggested, so that it can be used as an 
infallible substitute for hide powder. 

It is to be hoped that the International Conference of Leather 
Trades Chemists, which will be held in London on September 28 and 
29, 1897, will be productive of much good, and that its decisions will 
regulate the commercial analysis of tanning materials till revised by a 
future meeting. 

That this conference has high aims is shown by the following selec- 
tion of subjects to be considered : 

1. Standard method of drawing samples of (a) liquid extracts; (3) 
solid extracts, including gambier ; (<r) valonia ; (d) algarrobilla and 
divi-divi ; (<?) general tanning materials. 

2. Preparation of sample for analysis. 

3. Preparation of infusion. 

4. Method of determination of tanning matters. 

5. Standard means of color measurement. 

ELECTRIC TRANSMISSION OF POWER. 

The direct application of power to machines by electric motors is a 
subject which has latterly claimed a good deal of the attention of 
tanners, and a number of them have introduced the "direct drive" in 
their establishments with very satisfactory results. The designers and 
builders of the electric motors are the Northern Electrical Mfg. Co., 
Madison, Wis., and the claims they make for their appliances are 
obvious and well worth the examination of all users of machinery. 
They calculate that the motors save thirty per cent, of floor space, 
compared with line shaft transmission. A number of machines with 
line shafting use up nearly double the floor space they would otherwise 
occupy, and then they frequently are placed at great disadvantage with 
reference to the handling of raw material and the manufactured pro- 
duct, and in relation to other machines performing kindred work. 
With the "direct drive" each machine may be located absolutely at 
the will of the manufacturer. Besides the better arrangement of the 
mechanism, there is a large saving in hangers, shafts, belts, pulleys, etc., 
and also in power. It is estimated that in the average establishment 
there is a loss on power delivered from the engine of forty per cent. 



APPENDIX. 637 

The company claim that with their direct connection these losses 
should not exceed twenty per cent, of the total power delivered. 
When any machine is stopped, the consumption of power is stopped 
likewise. 

Direct electric motor drive is also claimed to yield a further material 
gain arising from the increase in the daily output of each driven ma- 
chine, and consequently a very material gain in the output per man 
throughout the entire force employed, thus greatly increasing the 
amount of manufactured product per dollar of wages paid. There is 
also an absolute control of speed. It may be made uniform or varied 
at will, thus enabling each machine to be operated at its most profitable 
speed. 

The tan drums of the Pfister & Vogel Leather Co., Milwaukee, are 
driven with these motors, and the company say they are giving perfect 
satisfaction. E. C. Fisher & Co., Gowanda, N. Y., have equipped their 
tannery complete with electrical generators and special tannery motors 
and fixtures, and say : 

" To say that we are pleased with the work you have done and the 
operation of your machinery, would scarce do the subject justice. We 
already note the manifest saving in power and labor through direct ap- 
plication of the power and the great convenience of placing the ma- 
chinery. We are much pleased with the strength, compactness and 
ease of operation of the equipments, all of which go from the first start 
without any trouble or hindrance. You have solved the economy 
question for the tanners of the world, and we heartily recommend your 
equipments to the trade." 

The Northern Electrical Manufacturing Co. have issued a useful 
pamphlet (catalogue No. 7) showing their devices as used in connec- 
tion with tanning machines of various descriptions, and it is replete 
with valuable information on the subject. 

TO DRESS STRAP, POCKET-BOOK, BAG, CASE AND WELT LEATHER AND 
FLEXIBLE SPLITS. 

Soak the stock so as to wet it through and skive off the rough flesh. 
Then jack the sides well on the grain in order to impart as much 
smoothness as possible. Then split them for any substance required. 
After they are split shave them ; afterward mill them ; for every twenty- 
five sides give them five to six pounds of borax for thirty minutes ; 
wash off clean ; then add sumac with two pails of well scalded sumac 



638 APPENDIX. 

with water enough to make the mixture twenty gallons ; add one pint 
of sulphuric acid to the sumac liquor and mill for two hours; wash off; 
give them one pound of oxalic acid dissolved in a pail of water ; mill 
ten minutes more and wash off; take the sides out and slick them off, 
they are then ready for coloring. If coloring is not desired they will 
make nice russet leather by giving them one pound of muriate of tin 
before slicking them out ; if the stock is for strap, half dry them and 
moss them well on the flesh, set them out well on the grain and tack 
them on frames ; stretch them well when they are dry, strip them from 
the frames, trim and moss them on the flesh and jack, hang up and 
dry, then dampen them with a weak oxalic acid on the grain and glass 
them out smoothly ; then give them a good seasoning of flaxseed ; hang 
up and dry ; when they are dry, roll them ; then brush or felt on the 
grain and they are finished. If bag or pocketbook stock is wanted the 
sides should not be mossed, because mossing stiffens them and bag 
leather should be seasoned with egg albumen and milk or starch and 
milk, one-half pound starch and one pint of milk. If two ounces of 
gum arabic are mixed with every pail of seasoning, a better finish will 
be imparted. If black stock is wanted use blood albumen, five ounces 
to the pail, more or less, according to the stock. If it is coarse, use 
more blood with a little milk ; when the stock is seasoned and dry, 
glaze it ; then dampen it well on the grain, pack the sides down, cover 
them up, put a weight on them and let them lie from five to ten hours ; 
then pebble them, and while they are damp grain them, hang up and 
dry ; when dry, glaze, grain and felt or brush and they are finished. 
The splits that come off these sides, if heavy enough, can be put into 
flexibles. Mill and sumac them as you would sides, but give them no 
muriatic acid, and when they are milled slick them on the flesh side ; 
when they are slicked out moss them on flesh, turn them over and 
slick them out well on the grain, and moss and tack them on the 
frames; when they are dry, trim, moss and jack both sides; then dry 
and they are finished. For welt leather skive the stock clean and jack 
the sides well, and then level them off with the machine ; give them a 
good scouring on both sides out of warm water; afterward a good 
sumac liquor for twenty-four hours at 140 F. ; slick them out half dry, 
then set out on the grain ; give them a weak oxalic acid and a water 
stuffing on the grain, turn them over, strike them out tight on the flesh 
and give them a light stuffing ; hang up when they are half dry, reset 
them and dry them out ; then glass and brush them on both sides, when 
they are finished. 



APPENDIX. 



639 



LIST OF PATENTS RELATING TO THE MANUFACTURE 

OF LEATHER, ISSUED BY THE GOVERNMENT OF 

THE UNITED STATES OF AMERICA, FROM 

JANUARY 1, 1884, TO AUGUST 31, 1897.* 



PROCESSES AND COMPOSITIONS. 



Extracts. 



Patents for extracting tan are classed with those for extracting dye 
woods or drugs, the processes being substantially similar, as well as 
much of the apparatus. The patents here cited refer only to tan bark. 



No. 


Date 




Inventor. 


Residence. 


302,105 


July 15. 


1884. 


Emile L. P. and Gus- 
tave C. Coez, 


St. Denis, France. 


393>976 


Dec. 4, 


1888. 


M. Gross, 


New York City. 


394J9 1 


Dec. 11, 


1888. 


J. H. Lorimer, 


Philadelphia, Pa. 


444,068 


Jan. 6, 


1891. 


J. and W. N. Hutchings, 


Warrington, England. 


466,152 


Dec. 29, 


1891. 


H. S. Blackmore, 


Mt. Vernon, N. Y. 


5 3.237 


Aug. 15, 


1893. 


M. Heftier and G. Ber- 
nard, 
S. W. Cochran, 


Paris, France. 


505,816 


Oct. 3, 


1893. 


Lambertville, N. J. 


510,132 


Dec. 5, 


1893. 


Otto C. Hagemann, 


New York City. 


541,410 


June 18, 


1895. 


W. Albach, 


Hochst, Germany. 


57I.635 


Nov. 17, 


1S96. 


John S. Adriance, 
Depilating. 


New York City. 


No. 


Date 




Inventor. 


Residence. 


291.953 


Jan. 15, 


1884. 


A. H. Stone, 


New York City. 


306,640 


Oct. 14, 


1884. 


P. H. P. Goulet, 


Reims, France. 


3i9.!36 


June 2, 


1885. 


E. Schroeder, 


San Francisco, Cal. 


322,521 


July 21, 


1885. 


T. R. Clark, 


New York City. 


33°.7 I 5 


Nov. 17, 


1885. 


S. R. Kennedy, 


Philadelphia, Pa. 


33°.79° 


Nov. 17, 


1885. 


S. R. Kennedy, 


Philadelphia, Pa. 


434»645 


Aug. 19, 


1890 


J. Schmitt, 


Allegheny, Pa. 


450,032 


April 7, 


1891. 


J. Perl, 


Berlin, Germany. 


481,516 


Aug. 23, 


1892 


R. L. Tudor, 


Cincinnati, 0. 


490,791 


Jan. 31, 


1893 


J. Mellinger, 


Waverly, Md. 


499. ! 34 


June 6, 


1893 


J. Mellinger, 


Baltimore, Md. 


5 1 9.345 


May 8, 


1894 


C. L. Puech, 


Mazamet, France. 


520,005 


May 15, 


1894 


J. Mellinger, 


Baltimore, Md. 


545,560 


Sept. 3, 


1895 


G. C. Walter, 


Hastings, Mich. 


555.°5° 


Feb. 18, 


1896 


Pierson and Moor, 


Philadelphia, Pa. 



*The first edition of this book, published November 22, 1884, contains the Lists 
of Patents issued by the Government from 1790 to 1883, inclusive. 



640 



APPENDIX. 



Bating. 



No. 


Date. 




Inventor. 


Residence. 


461,010 


Oct. 13, I 


891. 


C. W. Cooper, 


Brooklyn, N. Y. 


359»36o 


Mar. 15, 1 


887. 


E. P. Nesbit, 


Surrey, England. 


411,034 


Sept. 17, 


889 


A. Hull, 


West Winsted, Conn. 


4*3.615 


Oct. 22, i 


889. 


W. Dieterle, 


Feuerbach, Germany. 


444,77 * 


Jan. 13, 1 


891. 


M. Wilson, 


Becket, Mass. 


45°>93° 


April 21, i 


891 


W. Dieterle, 


Feuerbach, Germany. 


45°,954 


April 21, i 


891 


W. Oetlinger, 


Philadelphia, Pa. 


452,271 


May 12, ) 


891 


Hull and Burns, 


Boston, Mass. 


455,85* 


July 14, ] 


891 


H. Poydenot, 


Bayonne, France. 


549,* 93 


Nov. 5, 


895 


O. Geisler, 


Gloversville, N. Y. 


580,211 


April 6, 1 


897. 


W. Dieterle, 
Tanning. 


Feuerbach, Germany. 


No. 


Date 




Inventor. 


Residence. 


293,364 


Feb. 12, j 


884 


L. Schnadel, 


Chicago, 111. 


3°°,35 2 


June 17, 


884 


S. S. Eddy, 


Rochester, N. Y. 


302,132 


July 15, i 


884 


E. W. Hewitt, 


Louisville, Ky. 


304,958 


Sept. 9, ] 


884 


J. Roberts, 


Portville, N. Y. 


309,701 


Feb. 23, 


884 


S. S. Eddy, 


Rochester, N. Y. 


320,603 


June 23, 


885 


E. S. Ward, 


Newark, N. J. 


326,753 


Sept. 22, 


[885 


G. H. Leonard, 


Landisburg, ?a. 


338,182 


Mar. 16, 


[886 


A. Muller, 


New York City. 


350,706 


Oct. 12, 1 


886 


Mary Sutherland, 


Diamond, Mo. 


351,204 


Oct. 19, 


[886 


J. T. Rhyne, 


Durant, Mo. 


353,341 


Nov. 30, 


886 


H. L. Wilcox, 


Lincoln, Neb. 


375,455 


Dec. 27, 


887 


Millochau and Chailly, 


Paris, France. 


375,845 


Jan. 3, 


[888 


Waer, Phillips and 
Kengla, 


Tucson, Arizona. 


387,957 


Aug. 7, 


[888 


C. H. Perrin, 


Jefferson City, Mo. 


396,337 


Jan. 15, 


889 


J. Lalor, 


Independence, la. 


4*1,93* 


Oct. 1, 


889 


G. H. Russell, 


Newburg, Pa. 


411,932 


a 


i( 


" 


" 


435*922 


Sept. 9, 


[890 


T. L. Crafton, 


Sidney, Ark. 


447,427 


Mar. 3, 


891 


W. E. Hedges, 


Polk Bayou, Ark. 


448,420 


Mar. 17, 


1 891 


J. Engelke, 


Cincinnati, 0. 


450,121 


April 7, 


1891 


C. B. Warrand, 


Savannah, Ga. 


450,998 


April 21, 


[891 


W. Dieterle, 


Feuerbach, Ger. 


453,295 


June 2, 


[891 


J. T. Smith, 


San Francisco, Cal. 


459,993 


Sept. 22, 


1891 


H. Churchill, 


Rochester, N. Y. 


461,108 


Oct. 13, 


[891 


R. W. Turner, 


Dublin, Texas. 


464,423 


Dec. 1, 


[891 


Brown,Clark and Brown 


South Fork, Mo. 


473,8o5 


April 26, 


1892 


S. W. Wright, 


Mountain Grove, Mo 


504,013 


Aug. 29, 


1893 


W. Zahn, 


Newark, N. J. 


5*7,083 


Mar. 27, 


1894 


C. B. Warrand, 


Savannah, Ga. 


526,229 


Sept. 18, 


1894 


J. B. Hodges, 


Salem, Ark. 


528,427 


Oct. 30, 


1894 


D. A. Goodman, 


Salisbury, N. C. 


536,019 


Mar. 19, 


1895 


S. and G. Durio, 


Turin, Ttaly. 


539,488 


May 21, 


1895 


1 W. A. Ragland, 


Springfield, Mo. 


542,680 


June 16, 


[895 


H. A. Leverett, 


London, England. 


555,028 


Feb. 18, 


1896 


J. H. Thompson, 


Columbus, Ind. 


562,781 


June 23, 


1896 


J. Durio, 


Turin, Italy. 


564,086 


July 14, 


1896 


C. Knees, 


Oshawa, Canada. 



APPENDIX. 



64I 



Tawing.* 



No. 


Date 




Inventor. 


Residence. 


291,784 


Jan. 8, 


1884. 


A. Schultz, 


New York City. 


291,785 


Jan. 8, 


1884. 


A. Schultz, 


New York City. 


3 2 3.973 


Oct. 27, 


1885. 


G. F. Schweitzer, 


Lincoln, Neb. 


331.942 


Dec. 8, 


1885. 


T. R. Clark, 


New York City. 


340,199 


April 20, 


1886. 


S. J. Dobson, 


Lincoln, Neb. 


343.J66 


June 8, 


1886. 


J. W. Fries, 


Salem, N. C. 


343. 1 67 


June 8, 


1886. 


J. W. Fries, 


Salem, N. C. 


345.827 


July 20, 


1886. 


J. S. Bilwiller, 


St. Gall, Switzerland. 


349,5 8 9 


Sept. 21, 


1886. 


G. W. Hersey, 


Empire, Wis. 


367.H5 


July 26, 


1887. 


C. Kuestner, 


Magdeburg, Prussia. 


381,730 


April 24, 


1888. 


J. Townsend, 


Glasgow, Scotland. 


38i,734 


April 24, 


1888. 


Warter and Koegel, 


Newark, N. J. 


383,379 


May 22, 


1888. 


Snow and Howard, 


Wichita, Kansas. 


385.222 


June 26, 


1888. 


W. Zahn, 


Newark, N. J. 


389,150 


Sept. 4, 


1888. 


J. Hoelck, 


Chicago, 111. 


401,434 


April 1 6, 


1889. 


J. W. Hitt, 


Lisle, N. Y. 


401,715 


April 16, 


1889. 


Erik Olstad Ollestad, 


St. Paul, Minn. 


409.336 


Aug. 10, 


1889. 


L. Rappe, 


Newark, N. J. 


442,684 


Feb. 16, 


1890. 


A. F. Krueger, 


Kankakee, 111. 


451.385 


April 28, 


1891. 


J. H. McWhirter, 
Langley and Upton, 


Moody, Mo. 


455.674 


>ly 7. 


1891. 


G. C. Walter, 


Hastings, Mich. 


456,855 


July 28, 


1891. 


C. L. Royer, 


Halifax, England. 


472,701 


April 12, 


1892. 


H. Endemann, 


Brooklyn, N. Y. 


495,028 


April II, 


1893. 


M. Dennis, 


Brooklyn, N. Y. 


498,067 


May 23, 


1893. 


A. D. Little, 


Boston, Mass. 


498,077 


May 23, 


1893. 


W. M. Norris, 


Princeton, N. J. 


498,214 


May 23, 


1893. 


W. M. Norris, 


Princeton, N. J. 


501,586 


July 18, 


1893- 


J. W. Clayton, 


Barren Fork, Ark. 


504,012 


Aug. 29, 


1893. 


W. Zahn, 


Newark, N. J. 


504,014 


Aug. 29, 


i8 9 3- 


W. Zahn, 


Newark, N. J. 


506,696 


Oct. 17, 


1893. 


J. H. James, 


Nashville, Ark. 


511,007 


Dec. 19, 


1893. 


W. Zahn, 


Newark, N. J. 


511,301 


Dec. 19, 


1893. 


W. F. Lawley, 


Kennedy, Ala. 


511,411 


Dec. 26, 


1893. 


M. Dennis, 


Newark, N. J. 


518,467 


April 1 7, 


1894. 


W. M. Norris, 


Princeton, N. J. 


528,162 


Oct. 30, 


1894. 


C. Heipzerling, 


Frankfort- n - M a i n 
Germany. 


542,971 


July 16, 


1895. 


O. P. Amend, 


New York City. 


556,325 


Mar. 10, 


1896. 


S. P. Sadtler, 


Philadelphia, Pa. 


561,044 


May 26, 


1896. 


S. Chadwick, 


Philadelphia, Pa. 


563,559 


July 7. 


1896. 


T. E. Burlingame, 


Central Falls, R. I. 


563,560 


" 


" 


" 


" 


563,561 


n 


« 


" 


" 


564,106 


July 14, 


1896. 


J. C. Rogers, 


Cuero, Texas. 


573,362 


Dec. 15, 


1896. 


H. Schweitzer, 


Englewood, N. J. 


573,631 


Dec. 22, 


1896. 


G. W. Adler, 


Philadelphia, Pa. 


574,014 


Dec. 29, 


1896. 


Wagner and Maier, 


Philadelphia, Pa. 


579.000 


Mar. 16, 


1897. 


C. Marter, 


London, England. 


582,960 


May 18, 


1897. 


J. A. Schweitzer, 


Stains, France. 


588,874 


Aug. 24, 


1897. 


W. M. Norris, 


Princeton, N. J. 



*The conversion of hides and skins into leather by the aid of mineral substances. 
41 



642 



APPENDIX. 



No. 

337> 2 ^9 
399.893 
408,360 

449.437 
458,132 
467,200 
482,199 
526,769 
547.985 



No. 

341.583 
Reissue ) 
10,792 J 
361,999 
5 3,235 
5 3.987 
55 2 >497 



No. 

295,653 
325,320 
329,960 
346,581 
363,420 
365,854 
378,325 
381,680 

383,5" 
397,803 
401,390 
402,731 
405,763 

406,102 
406,901 
418,414 

425,919 
432,853 

438,470 
439,607 

441,010 

449,339 
451,427 
Reissue \ 
11,144/ 
458,828 
466,429 
469,385 
473,679 
474,702 



Date. 
Mar. 2, 1 886 
Mar. 9, 1889 
Aug. 6, 1889 
Mar. 31, 1891 
Aug. 18, 1 89 1 
Jan. 19, 1892 
Sep. 6, 1892 
Oct. 2, 1894 
Oct. 15, 1895 



Date. 
May 11, 1886. 

Dec. 21, 1886. 

April 26, 1887. 
Aug. 15, 1893. 
Aug. 29, 1893. 
Dec. 31, 1895. 



Currying. 

Inventor. 
J. A. J. Schultz, 
J. J. Hayward, 

A. Sommer, 
W. B. Davis, 

G. C. Seeberger, 
F. Riegert, 
J. Sanzenbacher, 
J. E. M. Bourgeois, 

B. P. Bradford, 

Preserving. 

Inventor. 
F. Latulip, 

F. Latulip, 

Grether and Mosher, 

F. Groguet, 

G. Ruemelin, 
E. Menowsky, 



Coloring and Polishing. 



Date. 
Mar. 25, 18 
Sep. 1, 18 
Nov. 10, 18 
Aug. 3, 18 
May 24, 18 
July 5, 18 
Feb. 21, 18 
April 24, 18 
May 29, 1888 
Feb. 12, 1889 
April 16, 1889 
May 7, 1889 
June 25, 18 
July 2, 18 
July 16, 18 
Dec. 31, 18 
April 15, 18 
July 22, 1890 

Oct. 14, 1890 
Jan. 28, 1890 
Nov. 18, 1890 
Mar. 31, 1891 
April 28, 1 89 1 

Feb. 10, i£ 

Sep. 1, 1 89 1 
Jan. 5, 1892 
Feb. 23, i£ 
April 26, 1892 
May 10, 1892 



Inventor. 
L. Klopfer, 
G. S. Colburn, 
A. Schmitt, 
E. Z. Coffee, 
J. Prickett, 
H. C. Parker, 
C. L. Leonard, 
L. C. Dewillers, 
A. S. Ashcroft, 
S. C. Howell, 
C. D. St. Pierre, 
E. Frid, 
G. H. Bishop, 
G. Langenhagen, 
W. E. Harter, 
G. T. Landauer, 
Wallace and Wallace, 
Baulch, Steele and 

Evans, 
W. W. Crooker, 
O. II. Shaw, 
J-M. Jolly, 
G. P. Tipton, ■ 
J. W. Foster, 

W. W. Crooker, 

G. H. Farthing, 
W. F. Sampson, 
W. W. Crooker, 
J. F. Thompson, 
J. E. Swain, 



Residence. 
St. Louis, Mo. 
Ballston, N. Y. 
Berkeley, Cal. 
Newport, N. Y. 
Munchberg, Germany. 
St. Joseph, Mo. 
Canfield, O. 
Paris, France. 
Worcester, Mass. 



Residence. 
Syracuse, N. Y. 

Syracuse, N. Y. 

South Bend, Ind. 
Bourbevoie, France. 
Milwaukee, Wis. 
New York City. 



Residence. 
Munich, Germany. 
Gardner, Mass. 
New Orleans, La. 
Philadelphia, Pa. 
Pittsfield, Mass. 
Wilmington, Del. 
Grafton, Mass. 
Brooklyn, N. Y. 
Brandenburg, Ky. 
Newark, N. J. 
Brooklyn, N. Y. 
New Hamburg, N. Y. 
Revere, Mass. 
Leipzig, Germany. 
West Nanticoke, Pa. 
Frankfort on Main,Ger. 
Clay Center, Neb. 
St. Louis, Mo. 

Lynn, Mass. 
Toms Brook, Va. 
Martin, Texas. 
Hot Springs, Ark. 
Detroit, Mich. 

Lynn, Mass. 

San Jose, Cal. 
Saugus, Mass. 
Lynn, Mass. 
Rockland, Mass. 
Baltimore, Md. 









APPENDIX. 


643 


No. 


Date. 


Inventor. 


Residence. 


492,836 


Mar. 7, 


1893. 


J. Riegert, 


St. Joseph, Mo. 


494,5 r 4 


Mar. 28, 


1893- 


J. F. Thompson, 


Rockland, Mass. 


S 01 ^ 11 


July 11, 


1893- 


Albertson and Briggs, 


Rockland, Mass. 


501,312 


July 11, 


1893. 


Albertson and Briggs, 


Rockland, Mass. 


5°4,S39 


Sep. 5, 


1893. 


Z. T. Fowler, 


Santa Rosa, Cal. 


536,966 


April 2, 


1895. 


R. Owens, 


Orleans, Cal. 


539>323 


May 14, 


1895. 


Woods and Maclay, 


Wurtsborough, N. Y. 


542,188 


July 2, 


1895. 


R. Ergang, 


Magdeburg, Germany. 


545,5°5 


Sep. 3, 


1895. 


F. A. Hurd, 


Red Bank, N. J. 


545,734 


Sep. 3, 


1895. 


J. Scholl, 


Brooklyn, N. Y. 


546,876 


Sep. 24, 


i895- 


J. B. Bernard, 


St. Paul, Minn. 


555.537 


Mar. 3, 


1896. 


Stevens and Schroeder, 


Arago, Oregon. 


57 2 .439 


Dec. 1, 


1896. 


Jane Moore, 


Cambridge, Mass. 


576,918 


Feb. 9, 


1897. 


A. L. Thompson, 


Rock Creek, 0. 


583,871 


June 1, 


1897. 


Travis and Early, 


Peabody, Mass. 


588,000 


Aug. 10, 


1897. 


Wm. M. Norn's, 


Princeton, N. J. 


588,471 


Aug. 17, 


1897. 


H. A. Quigley, 
APPARATUS. 

Coloring and Polishing. 


Milford, N. H. 


No. 


Date. 


Inventor. 


Residence. 


320,906 


June 30, 


1885 


F. B. Batchelder, 


Maiden, Mass. 


322,606 


July 21, 


1885 


J. Hodskinson, 


Salem, Mass. 


385,933 


July 10, 


1888 


I. G. Hooper, 


Newark, N. J. 


427,697 


May 13, 


1890 


J. Kristen, 


Brunn, Moravia. 


436,363 


Sep. 16, 


1890 


A. Travis, 


Gloversville, N. Y. 


442,628 


Dec. 23, 


1890 


T. J. Faulkner, 


Lynn, Mass. 


456,605 


July 28, 


1891 


A. Travis, 


Gloversville, N. Y. 


477,761 


June 28, 


1892 


C. Knabe, 


Osterwieck, Germany. 


498,120 


May 23, 


1893 


A. F. Jones, 


Salem, Mass. 


504,224 


Aug. 29, 


1893 


C. H. and A. A. Lappe, 


Allegheny, Pa. 


513,642 


Jan. 30, 


1894 


A. F. Jones, 


Salem, Mass. 


542,439 


July 9, 


1895 


Enos and Pratt, 


Peabody, Mass. 


578,060 


Mar. 2, 


1897 


C. E. House, 


Yates, Mich. 


579,141 


Mar. 23, 


1897 


R; N. Dunn, 
Leather Measuring. 


Philadelphia, Pa. 


No. 


Date. 


Inventor. 


Residence. 


329,596 


Nov. 3, 


1885 


W. A. Sawyer, 


Danversport, Mass. 


329,597 


Nov. 3, 


1885 


" 


" 


514,821 


Feb. 13, 


1894 


J. E. Fortin, 
Rossing Bark. 


Quebec, Canada. 


No. 


Date. 


Inventor. 


Residence. 


300,829 


June 24, 


1884 


F. F. Angermaier, 


Ravensburg, Wurtem 
berg, Germany. 


300,996 


June 24, 


1884 


F. Merziger, 


Trier, Prussia. 


305,322 


June 24, 


1884 


a 


a 


314,876 


Mar. 31, 


1885 


T. Poole and F. P. 
Snow, 


Orange, Mass. 


368,968 


Aug. 30, 


1887 


F. M. Purinton, 


Providence, R. I. 


379,559 


Mar. 20, 


1888 


N. H. Brokaw, 


Kaukauna, Wis. 


397,"4 


Feb. 5, 


1889 


N. H. Dolsen, 


St. Ignace, Mich. 


416,784 


Dec. 10, 


1889 


T. F. Horn, 


Livermore Falls, Me. 



644 




APPENDIX. 




No. 


Date. 


Inventor. 


Residence. 


431.154 


July # I, 1890. 


F. H. and A. E. Stearns, 


Eden, Vt. 


489,178 


Jan. 3, 1893. 


R. P. Bloss, 


Palmer, N. Y. 


489,251 


Jan. 3, 1863. 


W. Hadley and A. T. 
McDonald, 


Shelton, Conn. 


5 IO ,795 


Dec. 12, 1893. 


W. W. D. Jeffers, 


Ticonderoga, N. Y. 


5*5.537 


Feb. 12, 1894. 


A. E. Stearns, 


Eden, Vt. 


516,091 


Mar. 6, 1894. 


E. C. Hargreave, 


Bay City, Mich. 


517,990 


April 10, 1894. 


W.W. and F.N. Trevor, 


Lockport, N. Y. 


528,664 


Nov. 6, 1894. 


C. E. V. Folin, 


Hammerby, Sweden. 


528,873 


Nov. 6, 1894. 


W. Hadley, 


Shelton, Conn. 


540,980 


June 11, 1895. 


E. C. Hargreave, 


Bay City, Mich. 


572,948 


Dec. 15, 1896. 


A. E. Beals, 


Norwich, N. Y." 


579.946 


Mar. 30, 1887. 


P. Etches, 


Tupper Lake, N. Y. 




Grinding Mills for Bark. 




No. 


Date. 


Inventor. 


Residence. 


300,048 


June 10, 1884. 


L. B. Clark, 


Springfield, Mass. 


305.7" 


Sep. 23, 1884. 


J. T. Phillips, 


Grand Rapids, Mich. 


32I,7 2 5 


July 7, 1885. 


B. Holbrook, 


Kenosha, Wis. 


325,849 


Sep. 8, 1885. 


J. McKendrick, 


New York City. 


329.113 


Oct. 27, 1885. 


W. A. Woods, 


Santa Cruz, Cal. 


332,796 


Dec. 22, 1885. 


' J. C. Hagerty, 


a a ti 


332,797 


Dec. 22, 1885. 


" 


a a a 


332,854 


Dec. 22, 1885. 


W. A. Woods, 


Santa Cruz, Cal. 


334,859 


Jan. 26, 1886. 


J. C. Hagerty, 


a a it 


335,532 


Feb. 2, 1886. 


B. Ott, 


La Crosse, Wis. 


335.533 


Feb. 2, 1886. 


" 


tt tt a 


340,922 


April 27, 1886. 


ti 


ti a tt 


35M78 


Oct. 17, 1886. 


B. Holbrook, 


Milwaukee, Wis. 


355^79 


Dec. 28, 1886. 


R. C. Kirby, 
Tan Vats. 


Santa Cruz, Cal. 


No. 


Date. 


Inventor. 


Residence. 


308,803 


Dec. 11, 1884. 


R. Spitta, 


Brandenburg- on 
Havel, Prussia. 


321,300 


June 30, 1885. 


T. Johnston baugh, 


Clearfield, Pa. 


324,916 


Aug. 25, 1885. 


Bull and Hill, 


Limestone, N. Y. 


328,984 


Oct. 27, 1885. 


T. R. Tuttle, 


Salem, Mass. 


332,45 x 


Dec. 15, 1885. 


L. Simpson, 


Bellevue, Pa. 


380,890 


April 10, 1888. 


J. Head, 


York, Pa. 


386,488 


July 24, 1888. 


A. A. Myers, 


Lancaster, Pa. 


483,734 


Oct. 4, 1892. 


B. P. Bradford, 


Worcester, Mass. 


510,500 


Dec. 12, 1893. 


T. Clarke, 


Stockport, England. 


5 J 4,549 


Feb. 13, 1894. 


W. T. Harrison, 


Pooler, Ga. 


571,678 


Nov. 17, 1896. 


A. A. Myers, 
Endless Belts. 


Lancaster, Pa. 


No. 


Date. 


Inventor. 


Residence. 


H 1 ^ 


Nov. 24, 1885. 


A. W. Reid, 


Ballston Spa, N. Y. 


356,101 


Jan. 18, 1887. 


E. A. Curry, 


Winchester, Mass. 


389,5" 


Sept.'n, 1888. 


W. M. Hoffman, 


Detroit, Mich. 


479,072 


July 19, 1892. 


A. A. Hunting, 


Salem, Mass. 


497,°°3 


May 9, 1893. 


Dawson and Schu- 
macher, 


Boston, Mass. 


584,123 


June 8, 1897. 


W. B. Turner, 


Somerville, Mass. 







APPENDIX. 


645 






Splitting* 




No. 


Date. 


Inventor. 


Residence. 


291,641 


Jan. 1884 


T. S. Strong, 


East Bridgewater, Mass 


295,629 


Mar. 25, 1884 


H. S. Ginther, 


Olney, 111. 


295,787 


Mar. 25, 1884 


B. McKeen, 


Peabody, Mass. 


305,240 


Sept. 16, 1884 


J. A. Saff ord, 


Boston, Mass. 


306,760 


Oct. 24, 1884 


J. T. Krebs, 


Cleveland, O. 


319.357 


June 2, 1885 


G. L. Tyler, 


Lynn, Mass; 


332,385 


Dec. ic, 1885 


E. Cummings, 


Woburn, Mass. 


337> 82 ° 


Mar. 16, 1886 


A. E. Dodge, 


Woburn, Mass. 


339,990 


April 13, 1886 


J. A. Josselyn, 


Brookfield, Mass. 


342,983 


June 1, 1886 


G. L. Tyler, 


Lynn, Mass-. 


344,404 


June 29, 1886 


C. E. Roberts, 


Chicago, HI. 


345-oo7 


July 6, 1886 


G. L. Tyler, 


Lynn, Mass. 


346,389 


July 27, 1886 


A. F. Stowe, 


Worcester, Mass. 


347,402 


Aug. 17, 1886 


A. G. Webster, 


Boston, Mass. 


353,235 


Nov. 23, 1886 


A. F. Stowe, 


Worcester, Mass. 


358,081 


Feb. 22, 1887 


T. Smith, 


Cincinnati, 0. 


358,883 


Mar. 8, 1887 


C. E. Roberts, 


Chicago, 111. 


362,694 


May 10, 1887 


H. Worcester, 


Maiden, Mass. 


372,640 


Nov. 1, 1887 


C. E. Roberts, 


Chicago, 111. 


373,196 


Nov. 15, 1887 


C. E. Roberts, 


Chicago, 111. 


374,401 


Dec. 6, 1887 


G. Faustman, 


Philadelphia,- Pa. 


378,157 


Feb. 21, 1888 


W. E. Adams, 


Lynn, Mass. 


378,158 


" 


W. E. Adams, 


Lynn, Mass. 


378,179 


" 


S. Ross, Jr., 


Newport, Ky. 


378,185 


Feb. 21, 1888 


G. L. Tyler, 


Lynn, Mass. 


378,186 


" 


" 


it tt 


379,700 


Mar. 20, 1888 


A. Hull, 


New Boston, Mass. 


381,075 


April 10. 1888 


J. A. Josselyn, 


Brookfield, Mass. 


395,759 


Jan. 8, 1889 


H. Stanley, 


Swampscott, Mass. 


Reissue "^ 
11,008 j 


June 18, 1889 


H. Stanley, 


Swampscott, Mass. 


403,486 


Mar. 14, 1889 


H. C. Pease, 


Worcester, Mass. 


405,697 


June 25, 1889 


E. M. Dunphe and 
C. Blockhaus, 


East Bridgewater,Mass 


413,093 


Oct. 15, 1889 


f. A. Safford, 


Maiden, Mass.' 


420,152 


Jan. 28, 1890 


C. S. Fifield, 


Revere, Mass. 


445,744 


Feb. 3, 1 89 1 


W. A. Bates, 


Princeton, Me. 


462,166 


Oct. 27, 1891 


J. A. Safford, 


Maiden, Mass. 


465,145 


Dec. 15, 1891 


66 tt 


a a . 


477,456 


June 21, 1892 


66 66 


a it ' 


477,457 


" " 


66 66 


a a 


477,461 


" " 


66 66 


a «• 


477,462 


a a 


66 (t 


a a 


479,461 


July 26, 1892 


S. H. Randall, 


Wyoming, 0. 


5M,730 


Feb. 13, 1894 


J. A. Safford, 


Maiden, Mass. 


537,912 


April 23, 1895 


J. K. Bigelow, 


San Francisco, Cal. 


539,472 


May 21, 1895 


J. E. Fairbanks, 


Hillsdale, Mich. 


542,740 


July 16, 1895. 


J. Robertson, 


Woburn, Mass. 


554,783 


Feb. 18, 1896 


M. Leidgen, 


Milwaukee, Wis. 


561,360 


June 9, 1896. 


T. J. Bringham, 


Chicago, 111. 


587,783 


Aug. 10, 1897 


" " 


tt a 


587,784 


Aug. 10, 1897 


" " 


" " 


588,928 


Aug. 24, 1897 


G. R. Rank, 


Alleghany, N. Y. 



* Including machines used in shoe factories. 



646 



APPENDIX. 



Cutting, including Skiving* etc. 



No. 

296,219 
296,781 

297.351 
299,329 
299,952 
302,759 

304,824 
307,127 

310.527 
310,742 
312,643 
313^67 
313,172 

313,349 
3H,474 
316,006 
316,073 
316,074 
316,704 

317,463 
320,209 
322,923 
323,061 
323,860 
325, 37 
328,317 
331,293 
334,n9 
338,347 
343,238 
346,093 
346,651 
35o,753 
352,139 
356,662 

356,793 
358,067 

358,779 
361,707 
362,412 
363,265 
363,461 
364,643 
367,709 
368,108 
368,672 

370,327 
373,!26 
375,372 
375,8" 
376,974 



Date. 
April I, iS 
April 15, 1 c 
April 22, 1 i 
May 27, i£ 
June 10, i£ 
July 27, i£ 

Sep. 9, i<: 
Oct. 28, 1 1 
June 6, ll 
Jan. 13, 1* 
Feb. 24, 1 1 
Mar. 3, i£ 



Mar. 24, 1885. 
April 21, 1885. 



April 28, 
May 5, 
June 16, 
July 28, 
July 28, 
Aug. 4, 
Aug. 25, 
Oct. 13, 
July 28, 
Jan. 12, 
Mar. 23, 
June 8, 
July 27, 
Aug. 3, 
Oct. 12, 
Nov. 9, 
Jan. 25, 
Feb. 1, 



Feb. 22, 

Mar. 1, 
April 26, 
May 3, 
May 17, 
May 24, 
June 14, 
Aug. 2, 
Aug. 8, 
Aug. 23, 
Sept. 20, 
Nov. 15, 
Dec. 27, 
Jan. 3, 
Jan. 24, 



886 
886 



886 
886 
886 



887 



8S7 



Inventor. 
J. Roth, 

C. E. Ramus, 
G. W. Cody, 
H. A. Behn, 
R. Brownson, 

A. Miller and J. M. 

Kailer, 
E. Johnson, 
W. Lufkin, 
H. E. Koepka, 
G. E. Stockwell, 

D. Knox, 
R. Bowden, 

N. W. Calhoun and J. 
G. Chambers, 

F. R. Lewis, 
T. M. Platts, 
J. H. Busell, 

C. F. Stackpole, 

C. F. Stackpole, 
J. M. Watson, 

D. Knox, 

E. F. Belding, 
T. Gingras, 

J. Murphy, 

M. V. Doyle, 

Abbott and Luce, 

J. Kirwin, 

T. Gingras, 

J. D. Plunphrey, 

C. T. Grilley, 

H. G. Foss, 

H. H. Cummings, 

G. W. Cross, 

E. A. Latham, 
J. Leuenberger, 
T. B. Raymond, 

J. W. Ringrose, and 

D. A. Hauck, 
J. Parker and N. L. 

Gunning, 
N. B. Jones, 
J. Matthieu, 
W. E. Adams, 
J. N. Whitcomb, 
C. B. Hatfield, 
A.' D. Goetz, 

F. Engel and C. Wagner, 
H. Parsons, 

W. C. James, 
W. S. Fitzgerald, 
J. Burger, 

G. Marsh, 
E. Gott, 

C. Wonderlich, 



Residence. 
Columbus, O. 
Chicago, 111. 
Hartford, Conn. 
Union, N. J. 
St. Paul, Minn. 
Newark, O. 

New Orleans, La. 
Chelsea, Mass. 
St. Johnsbury, Vt. 
Marblehead, Mass. 
Lynn, Mass. 
Marblehead, Mass. 
Lena, 111. 

Troy, N. Y. 
Newark, N. J. 
Boston, Mass. 
Lynn, Mass. 
Lynn, Mass. 
Sharon, Mass. 
Lynn, Mass, 
Fitchburg, Mass. 
Buffalo, N. Y. 
Brooklyn, N. Y. 
Rockford, 111. 
Dedham, Mass. 
New York City. 
Buffalo, N. Y. 
Towanda, Pa. 
Boston, Mass. 
Auburn, Me. 
Maiden, Mass. 
Oxford, N. J. 
East Bridgewater,Mass. 
Camden, O. 
Rochester, N. Y. 
Mechanicsburg, 111. 

Williamsport, Pa. 

Murfreesboro, 111. 
Ottawa, 111. 
Lynn, Mass. 
Brockton, Mass. 
Rochester, N. Y. 
Martinsburg, Pa. 
Offenbach on Main,Ger. 
Marlboro, Mass. 
Boston, Mass. 
Boston, Mass. 
Cincinnati, O. 
Nashville, Tenn. 
Newton, Mass. 
Washington, Mo. 



* Including machines used in shoe factories. 









APPENDIX. 


<Hi 


No. 


Date 




Inventor. 


Residence. 


381,696 


April 24, 


1888. 


F. Hirsch, 


New York City. 


384,020 


June 5, 


1888. 


P. B. Clark and G. J. 
Klingler, 


Brooklyn, N.Y. 


384,032 


June 5, 


1888. 


F. E. Frost, 


Lewiston, Me. 


386,051 


July 10, 


1 888. 


G. H. Avery, 


East Hampton, Mass. 


390,5s 1 


Oct. 2, 


1888. 


E. F. Belding, 


Fitchburg, Mass. 


391,190 


Oct. 16, 


1888. 


S. H. Randall, 


Wyoming, 0. 


39 I >575 


Oct. 23, 


1888. 


C. H. Bayley, 


Boston, Mass. 


392,673 


Nov. 13, 


1888. 


A. D. Goetz, 


Martinsburg, Pa. 


394,iii 


Dec. 4, 


1888. 


O. G. Garlock, 


Palmyra, N. Y. 


399,965 


Mar. 19, 


1889. 


J. Bradley, 


Dundee, N. Y. 


403,805 


May 21, 


1889. 


S. Walder, 


Buda-Pesth, Hungary. 


404,949 


June 11, 


1889. 


G. H. Avery, 


East Hampton, Mass. 


412,503 


Oct. 8, 


1889. 


W. H. Hoople, 


Brooklyn, N. Y. 


417,268 


Dec. 17, 


1889. 


J. G. McCartee, 


Boston, Mass. 


419,357 


Jan. 14, 


1890. 


C. E. Ramus, 


Chicago, 111. 


421,778 


Feb. 18, 


189c. 


H. G. Starr, 


Belvedere, 111. 


423,977 


Mar. 25, 


1890. 


A. D. Wortben, 


Sandown, N. H. 


426,251 


April 22, 


1890. 


G. F. Dunn, 


Brockton, Mass. 


426,577 


April 29, 


1890. 


V. T. Whittlesey and 
A. B. Keyes, 


New Haven, Conn. 


427,461 


May 6, 


1890. 


H. Comstock, 


Fulton, N. Y. 


427,579 


May 13, 


1890. 


F. L. Kubn, 


Lunenburg, Mass. 


427,610 


May 13, 


1890. 


H. C. Pretty, 


Leicester, England. 


430,882 


June 24, 


1890. 


J. O. Purnell, 


Pittsfield, Mass. 


432,641 


Feb. 22, 


1890. 


C. F. Ramus, 


Chicago, 111. 


435,38! 


Aug. 26, 


1890. 


H. T. Rohrmoser, 


Hoboken, N. J. 


439,208 


Oct. 28, 


1890. 


A. J. Tewksbury, 


Haverhill, Mass. 


439,433 


Oct. 28, 


1890. 


J. R. Scott, 


Nyack, N. Y. 


439,6o3 


Oct. 28, 


1890. 


Randall. 




442,399 


Dec. 9, 


1890. 


J. A. Safford, 


Maiden, Mass. 


442,996 


May 26, 


1891. 


B. F. Durham, 


Brockton, Mass. 


443,579 


Dec. 30, 


1890. 


S. Hainkel, 


Quincy, 111. 


443,409 


Dec. 23, 


1890. 


J. R. Scott, 


Nyack, N. Y. 


445,588 


Feb. 3, 


1891, 


H. C. Pease, 


Worcester, Mass. 


453,944 


June 9, 


1891. 


J. R. Scott, 


New York City, 


458,535 


Aug. 25, 


1891. 


W. H. Kimball, 


Burlington, N. J. 


459,231 


Sept. 8, 


1891. 


C. S. Fifield, 


Revere, Mass. 


459,715 


Sept. 15, 


1891. 


S. J. Talbott, 


Milford, N. H. 


465,840 


Dec. 29, 


1891. 


A. Dewees and R. P. 
Trist, 


Brooklyn, N. Y. 


467,441 


Jan. 19, 


1892. 


J. R. Scott, 


New York City. 


468,613 


Feb. 9, 


1892. 


R. P. Trist, 


Wilmington, Del. 


470,015 


Mar. 1, 


1S92. 


J. R. Scott, 


New York City. 


470,016 


" 


" 


" 


" 


472,148 


April 5, 


1892. 


A. J. Tewksbury, 


Haverhill, Mass. 


475,053 


May 17, 


1892. 


L. M. Cabana, 


Buffalo, N. Y. 


477,458 


June 21, 


1892. 


J. A. Safford, 


Maiden, Mass. 


477,459 


" 


" 


" 


" 


479,583 


July 26. 


, 1892. 


C. H. Bayley, 


Boston, Mass. 


486,813 


Nov. 22, 


1892. 


A. K. Washburn, 


Bridgewater, Mass. 


487,894 


Dec. 13, 


1892. 


J. H. Shields, 


Chicago, 111. 


488,212 


Dec. 20, 


1892. 


H..Masterson, 


Jefterson City, Mo. 


488,324 


Dec. 20, 


1892. 


P. W. Rodecker, 


Sidney, 0. 


492,342 


Feb. 21 


, 1893. 


T. F. Tyler, 


Lynn, Mass. 


492,640 


Feb. 28, 


. 1893- 


T. Thompson, 


New London, Wis. 


493,i89 


Mar. 7. 


, 1893. 


J. L. Scott, 


New York City. 



648 






APPENDIX. 




No. 


Dat< 




Inventor. 


Residence. 


5°0»538 


July 4. 


1893. 


A. J. Allen, 


Essex, Canada. 


501,207 


Sept. 11, 


1893. 


T. Gingras, 


Buffalo, N. Y. 


503,341 


Aug. 15, 


1893. 


M. E. Briggs, 


St. Louis, Mo. 


505,198 


Sept. 19, 


1893. 


C. S. Fifield, 


Revere, Mass. 


505,598 


Sept. 26, 


l8 9 3- 


Z. T. French and W. 
T. Meyer, 


Boston, Mass. 


506,573 


Oct. 10, 


1893. 


J. M. Watson, 


Sharon, Mass. 


507,210 


Oct. 24, 


1893. 


A. Buchholz, 


Boeuf Creek, Mo. 


5 J 2 .953 


Jan. 16, 


1894. 


J. Gerber, 


Tremont, Mich. 


515.927 


Mar. 6, 


1894. 


E. B. Stimpson, 


Brooklyn, N. Y. 


517.631 


April 3, 


1894. 


A. J. Tewksbury, 


Haverhill, Mass. 


518,774 


April 24, 


1894. 


C. H. Bayley, 


Boston, Mass. 


518,790 


April 24, 


1894. 


A. E. Perry, 


Wakefield, Mass. 


5*9.570 


May 8, 


1894. 


H. A. Dodge and W. 
T. Richards, 


Newton, Mass. 


5 2 °. 2I 5 


May 22, 


1894. 


T. A. Norris, 


Brockton, Mass. 


520,709 


May 29, 


1894. 


J. R. Scott, 


New York City. 


520,851 


June 5, 


1894. 


J. R. and 0. Kempfe, 


Brooklyn, N. Y. 


521,048 


June 5, 


1894. 


M. J. Ryan, 


New Orleans, La. 


521,068 


June 5, 


1894. 


H. Wright, 


Kettering, England 


521,077 


June 5, 


1894. 


J. Barker, 


Philadelphia, Pa. 


521,090 


June 5, 


1894. 


J. R. Scott, 


New York City. 


5 21 .538 


June 19, 


1894. 


P. Goldstein, 


Newark, N. J. 


5 21 .583 


June 19, 


1894. 


G. A. Cole and E. H. 
Taylor, 


Lynn, Mass. 


525,872 


Sept. 11, 


1894. 


E. B. Stimpson, 


Brooklyn, N. Y. 


524,768 


June 21, 


1894. 


Randall. 




526,617 


Sept. 25, 


1894. 


F. E. Druschkey and 
L. A. Schyerling, 


Chicago, 111. 


527,299 


Oct. 9, 


1894. 


F. L. Stone, 


Brockton, Mass. 


527,928 


Oct. 23, 


1894. 


C. H. Baylev, 


Boston, Mass. 


528,448 


Oct. 30, 


1894. 


J. R.Scott,' 


New York City. 


528,502 


Oct. 30, 


1894. 


W. E. Bennett, 


Boston, Mass. 


531,069 


Dec. 18, 


1894. 


L. K. Scotford, 


Chicago, 111. 


531,744 


Jan. 1, 


1895. 


T. A. Norris, 


Brockton, Mass. 


53L949 


Jan. 1, 


1895. 


J. N. Kendall, 


Nashua, N. H. 


534,767 


Aug. 21, 


1894. 


Randall. 




535.784 


Mar. 12, 


1895. 


L. T. Barber, 


Boston, Mass. 


535.895 


Mar. 19, 


1895. 


B. F. Hale, 


Newburyport, Mass. 


537.H8 


April 9, 


1895- 


J. B. Gathright, 


Louisville, Ky. 


537.913 


April 23, 


I895- 


J. K. Bigelow, 


San Francisco, Cal. 


541.304 


June 18, 


1895. 


P. Young, 


Danbury, Conn. 


541,691 


June 25, 


1895- 


J. R. Scott, 


New York City. 


543.635 


July 3°. 


1895- 


A. S. Vose, 


Providence, R. I. 


543.792 


July 3°. 


i8 9 5- 


R. Wright and J. E. 
Parker, 


Chicago, 111. 


548,101 


Oct. 15, 


1895. 


S. Ward, 


Princeton, Ind. 


549,027 


Oct. 29, 


1895- 


J. R. Scott, 


Chicago, 111. 


549,216 


Nov. 5, 


1895. 


E. Sawyer, 


Barre, Vt. 


550.805 


Dec. 3, 


1895. 


E. Stimpson. 




55 J .87 2 


Dec. 24, 


1895. 


W. A. Murray and H. 
Fitzsimmons, 


Newark, N. J. 


554.o69 


Feb. 4, 


1896. 

V 


L. H. Liebe and J. A. 
Vanderpool, 


San Jose, Cal. 


557.276 


Mar. 31, 


1896. 


W. B Keighley, 


Vineland, N. J. 


557.554 


April 7, 


1896. 


E. V. Clemens, 


New York City. 



APPENDIX. 



649 



No. 
558,864 
560,782 
561,999 
562,000 
562,126 
564,889 

5 6 7>!3° 
5 6 7> J 3i 

570,164 
57^291 
571,292 

57 I » 2 93 

571.295 

573,274 
575,821 

578,547 
580,390 
586,308 



No. 
308,171 
318,820 

33!,325 
352,024 
Reissue ) 
10,860 f 
378,066 

387,305 
387,402 
388,611 
392,141 
393,544 
395,727 
396,811 
397,821 
402,860 
416,918 
423,030 
423,846 
457,136 
457,331 
501,593 
538,9H 
549,422 

549,423 
549,424 
553,682 

553,683 
580,865 
582,774 
585,212 



Date. 
April 21, 1896. 
May 26, 1896. 
June 16, 1896. 



July 28, 1896. 
Sep. 8, 1896. 

Sep. 8, 1896. 

Oct. 27, 1896. 
Nov. 10, 1896. 



Dec. 15, 1896. 
Jan. 26, 1897. 
Mar. 9, 1897. 
April 13, 1897. 
July 13, 1897. 



Inventor. 
E. Van Osla, 
J. Crydermann, 
W. Kootz, 
W. Kootz, 
H. Ellis, 

E. Rahm, 

P. Goldstein and G. 

Andae, 
P. Goldstein and G. 

Andae, 

F. J. Freese, 
A. L. Sweet, 



H. Le Roy Kemp, 
H. F. Blake, 
E. F. Davenport, 
J. H. Giffard, 
B. F. Dunham, 



Putting Out and Stretching. 

Date. Inventor. 

Nov. 18, 1884. R. S. Jennings, 

June 26, 1885. Stone and Pratt, 

Dec. 1, 1885. B. M. Plummer, 

Nov. 2, 1886. P. A. Jesson, 

Aug. 23, 1887. P. A. Jesson, 

Feb. 14, 1888. W. M. Hoffman, 

Aug. 7, 1888. J. F. Ingraham, 

Aug. 7, 1888. G. E. Danforth, 

Aug. 28, 1888. W. E. Adams, 

Oct. 30, 1888. N. Weber, 

Nov. 27, 1888. P.H.Daley, 

Jan. 8, 1889. N. Weber, 

Jan. 29, 1889. G. E. Danforth, 

Feb. 12, 1889. F. Storch, 

May 7, 1889. C. T. Royer, 

Dec. 10, 1889. M. N. Howard, 

Mar. 11, 1890. G. E. Danforth, 

Mar. 18, 1890. West and Sinning, 

Aug. 4, 1891. C. R. Stackpole, 

Aug. 4, 1891. G. V. Anderson, 

July 18, 1893. C. R. Stackpole, 

May 7, 1895. R - Holmes, 

Nov. 5, 1895. G - w - Baker, 

Nov. 5, 1895. G - w - Baker, 

Nov. 5, 1895. G - w - Baker, 

Jan. 25, 1896. L. Lichtenstein, 

Jan. 25, 1896. L. Lichtenstein, 

April 20, 1S97. G. V. Hysore, 

May 18,1897. C. Bouteon, 

Jan. 29, 1897. A. F. Jones, 



Residence. 
Louisville, Ky. 
Milwaukee, Wis. 



St. Catherines, Can. 
Elberfeld, Germany. 
Newark, N. J, 

Newark, N. J. 

Montreal, Canada. 
Chicago, 111. 



Camden, N. J. 
Haverhill, Mass. 
Boston, Mass. 
Grand Rapids. Mich. 
Brockton, Mass. 



Residence. 
Boston, Mass. 
Salem, Mass. 
Philadelphia, Pa. 
Paris, France. 

Paris, France. 

Detroit, Mich. 
West Peabody, Mass. 
Lynn, Mass. 
Lynn, Mass. 
Lynn, Mass. 
Lynn, Mass. 
Lynn, Mass. 
Lynn, Mass. 
Chicago, 111. 
Halifax, England. 
Brooklyn, N. Y. 
Lynn, Mass. 
St. Louis, Mo. 
Lynn, Mass. 
Wilmington, Del. 
Lynn, Mass. 
Cramer's Hill, N. J. 
Wilmington, Del. 
Wilmington, Del. 
Wilmington, Del. 
Wilmington, Del. 
Wilmington, Del. 
Wilmington, Del. 
Paris, France. 
Salem, Mass. 



650 






APPENDIX. 

Stretching Frames. 




No. 


Date. 


Inventor. 


Residence. 


308,170 


Nov. 18, 


1884. 


R. S. Jennings, 


Boston, Mass. 


335*595 


Feb, 9, 


1886. 


A. C. Krueger, 


Chicago, 111. 


357.609 


Feb. 15, 


1887. 


H. G. Landers, 


Protem, Mo. 


372,228 


Dec. 6, 


1887. 


J. Young, 


Newark, N. J. 


410,745 


Sept. 10, 


1889 


G. F. Stengel, 


Newark, N. J. 


414,283 


Nov. 5, 


1889. 


B. P. Bradford, 


Worcester, Mass. 


44o,35 8 


Nov. 11, 


1890. 


P. King, 


Washington, D. C. 


44b, 794 


Feb. 8, 


1891. 


W. Coupe, 


Attleboro, Mass. 


446,847 


Feb. 24, 


1891. 


H. R. Behrens, 


Worcester, Mass. 


468,392 


Feb. 9, 


1892. 


H. R. Behrens, 


Worcester, Mass. 


484>i37 


Oct. 11, 


1892. 


L. F. Cauffield, 


Ashtabula, 0. 


490,338 


Jan. 24, 


i893- 


L. F. Cauffield, 


Ashtabula, O. 


49o,339 


Jan. 24, 


1893. 


L. F. Cauffield, 


Ashtabula, 0. 


501,920 


July 25, 


1893- 


J. M. Charnock, 


Boston, Mass. 


5 ! 3,943 


Jan. 30, 


1894. 


P. King, 


Washington, D. C. 


536,456 


Mar. 26, 


1895 


J. W. Chapman, 


Detroit, Mich. 


546,089 


Sept. 10, 


1895 


Cook and Houston, 
Reciprocating Tools. 


San. Francisco, Cal. 


No. 


Date 




Inventor. 


Residence. 


299,893 


June 3, 


1884 


W. H. Wood, 


Woburn, Mass. 


305,532 


Sep. 23, 


1884 


J. A. Panton, 


Quincy, Mass. 


3!3>23i 


Mar. 3, 


1885. 


J. A. Panton, 


Quincy, Mass. 


325,675 


Sep. 8, 


1885 


S. Haley, 


Bramley, Leeds, Eng 
land. 


340,713 


April 27, 


1886. 


J. T. Freeman, 


Woburn, Mass. 


343,552 


June 8, 


1886 


Tyghe and Howell, 


Boston, Mass. 


354,178 


Dec. 14, 


1886. 


A. M. Bowers, 


Newark, N. J. 


363,585 


May 24, 


1887 


A. M. Bowers, 


Newark, N. J. 


372,507 


Nov. 1, 


1887 


G. W. Baker, 


Wilmington, Del. 


380,239 


Mar. 27, 


1888 


G. V. Anderson, 


a a 


391,221 


Oct. 15, 


1888. 


G. V. Anderson, 


it a 


394,750 


Dec. 18, 


1888 


G. W. Baker, 


it a 


405,653 


June 18, 


1889. 


G. W. Baker, 


a it 


426,225 


April 22, 


1890. 


G. W. Anderson, 


11 11 


441,821 


Dec. 2, 


1890 


J. A. Brownwell, 


Binghamton, N. Y. 


443,896 


Dec. 30, 


1890 


B. D. Chalkley, 


Richmond, Va. 


451,096 


April 28, 


1891. 


P. W. Whittier, 


North Andover, Mass, 


479,46o 


July 26, 


1892 


0. Potelune, 


Limoges, France. 


484,029 


Oct. 11, 


1892. 


L. E. Learoyd, 


Danvers, Mass. 


486,194 


Nov. 15, 


1892 


P. W. Minor, 


Springville, N. Y. 


490,443 


Jan. 24, 


1893 


F. C. Kimball, 


Salem, Mass. 


531,462 


Dec. 25, 


1894. 


G. Geyer, 


Brooklyn, N, Y. 


546,263 


Sep. 10, 


1895 


I. Vaughn, 


Salem, Mass. 


559,976 


May 12, 


1896. 


J. Hall, 


Leeds, England. 


561,583 


June 9, 


1896. 


J. Hall. 


Leeds, England. 


569,843 


Oct. 20, 


1896. 


H. Smith, 


Newark, N. J. 


589,123 


Aug. 31, 


1897. 


E. T. Ems, 
Rocking Frames. 


Philadelphia, Pa. 


No. 


Date 




Inventor. 


Residence. 


333,196 


Dec. 29, 


1885 


E. E. Church, 


Beddington, Me. 


339,134 


April 6, 


1886 


A. M. Bowers, 


Newark, N. J. 


346,900 


Aug. 10, 


1886 


P. Diehl, 


Gloversville, N. J. 









APPENDIX. 


651 


No. 


Datt 




Inventor. 


Residence. 


365.963 


July 5. 


1887. 


A. M. Bowers, 


Newark, N. J. 


366,298 


July 12, 


1887. 


tt tt 


tt H 


367»95 2 


Aug. 9, 


1887. 


" " 


tt tt 


392,004 


Oct. 30, 


1888. 


" " 


It It 


437.483 


Sep. 30, 


1890. 


T. P. Combs, 


Woburn, Mass. 


448,422 


Mar. 17, 


1891. 


Gafney and Dawson, 


Lynn, Mass. 


556,162 


Mar. 10, 


1896. 


T. J. Quinn, 


Stoneham, Mass. 


589,103 


Aug. 31, 


1897. 


C. A. Southwick, 
Rotating Tools. 


Peabody, Mass. 


No. 


Date 




Inventor. 


Residence. 


292,723 


Jan. 29, 


1884. 


A. Winchester, 


Rochester, N. Y. 


3°6,737 


Aug. 21, 


1884. 


M. Garniel, 


Paris, France. 


387.903 


Aug. 14, 


1888. 


A. Ott, 


Milwaukee, Wis. 


427,101 


May 6, 


1890 


P. Monk, 


Cincinnati, O. 


444,164 


Jan. 6, 


1891 


J. W. Vaughn, 


Salem, Mass. 


463.592 


Nov. 17, 


1891 


W. S. Bacon, 


Philadelphia, Pa. 


489,641 


Jan. 10, 


1893 


A. Probst, 


Worms, Germany. 


491,446 


Feb. 7, 


1893 


Pullman and Smith, 


Godalming, England. 


517,424 


Oct. 16, 


1894 


Hartman and Thomson, 


Offenbach on Main,Ger. 


527,889 


Oct. 23, 


1894 


L. and A. Schmoll, 


Newark, N. J. 


564.5" 


July 21, 


1896 


E. D. Evans, 
Rotary Cylinders. 


Bristol, Eng. 


No. 


Date 




Inventor. 


Residence. 


293.3° 8 


Feb. 12, 


1884 


A. Cerf. Lanzenburg, 


Paris, France. 


316,167 


April 21, 


1885 


F. J. Nelson, 


Boston, Mass. 


3 I 7>77° 


May 12, 


1885 


G. A. Hardy, 


Old Lenton, England. 


325.43 1 


Sept. 1, 


1885 


F. H. Meyers, 


Philadelphia, Pa. 


3 2 7. x 38 


Sept. 20, 


1885 


H. R. Churchill, 


Buffalo, N. Y. 


335^98 


Feb. 2, 


1886 


W. M. Hoffman, 


Buffalo, N. Y. 


367.257 


July 26, 


1887 


A. E. Whitney, 


Winchester, Mass. 


372.585 


Nov. 1 , 


1887 


J. Wayland, 


Newark, N. J. 


377.473 


Feb. 7, 


1888 


G. V. Anderson, 


Wilmington, Del. 


386,667 


Jan. 26, 


1888 


H. Thurlow, 


Skaneateles, N. Y. 


413,601 


Oct. 22, 


1889 


H. E. Freudenberg, 


Wenheim, Baden, Ger. 


417.251 


Dec. 17, 


1889 


Klinik, Penkowski and 
Gross, 


Konigshutte, Germany 


430.165 


June 17, 


1890 


A. C. Andrews, 


Chicago, 111. 


449.707 


April 7, 


1891 


T. Shaw, 


Vanceboro, Me. 


451,486 


May 5, 


1891 


A. R. Hutting, 


Salem, Mass. 


466,182 


Dec. 29, 


1891 


E. C. Northrup, 


Bodines, Pa. 


5 7.3H 


Oct. 24, 


1893 


W. Evans, 


Philadelphia, Pa. 


525.372 


Sept. 4, 


1894 


I. Vaughn, 


Salem, Mass. 


535.493 


Sept. 4, 


1894 


W. Evans, 


Philadelphia, Pa. 


577,402 


Feb. 16, 


1897 


H. Bright, 


Costello, Pa. 


58o,353 


April 6, 


1897 


I. Vaughn, 

Rolling and Embossing. 


Salem, Mass. 


No. 


Date 




Inventor. 


Residence. 


294,410 


Mar. 4, 


1884 


T. Shaw, 


Bangor, Me. 


295,948 


April 1, 


1884 


W. A. Sawyer, 


Danversport, Mass. 


310,160 


Dec. 30, 


1884 


W. C. Yaeger, 


Brownstown, Wis. 


311,498 


Feb. 3, 


1885 


D. Knox, 


Lynn, Mass. 


312,272 


Feb. 17 


1885 


W. W. Hubbard, 


Manchester, N. H. 



No. 


Dat< 




Inventor. 


Residence. 


337.935 


April 13, 


1886. 


A. M. Bowers. 


Newark, N. J. 


356,677 


Jan. 25, 


1887. 


J. Boyle, 


Peabody, Mass. 


393.486 


Jan. 27, 


1888. 


M. Scott, 


Newark, N. J. 


444,172 


Oct. 6, 


1 891. 


J. W. Vaughn, 


Salem, Mass. 


447,180 


Feb. 24, 


1891. 


E. Hayes, 


Lynn, Mass. 


466,083 


Dec. 20, 


1891. 


J. A. Safford, 


Maiden, Mass. 


462,825 


Nov. 10, 


1891. 


M. Scott. 


Newark, N. J. 


479,46o 


June 21, 


1892. 


* J. A. Safford, 


Maiden, Mass. 


552,857 


Jan. 7, 


1896. 


M. Scott, 
Tables and Frames. 


Newark. N. J. 


No. 


Date 




Inventor. 


Residence. 


291,882 


Jan. 15, 


1884. 


T. L. Daheny, 


Boston, Mass. 


333.773 


Jan. 5, 


1886. 


G. Middlemas, 


San Francisco, CaL 


340,712 


April 27, 


1886. 


J. T. Freeman, 


Woburn, Mass. 


352,955 


Nov. 23, 


1886. 


T. W. McKee, 


Towanda, Pa. 


362,286 


May 3, 


1887. 


G. A. Knox, 


Lynn, Mass. 


457> OI 4 


Aug. 4, 


1891. 


B. Schnepp, 


Louisville, Ky. 


547.762 


Oct. 15, 


1895. 


G. F. Bogel, 


Altoona, Germany. 


584,668 


June 15, 


1897. 


J. A. Brownell, 
Tumbling Drums. 


Binghamton, N. Y. 


No. 


Date 




Inventor. 


Residence. 


302,454 


July 22, 


1884. 


E. S. Ward, 


Newark, N. J. 


308,755 


Dec. 2, 


1884. 


E. D. Solminehac, 


Lorient, France. 


3I3.47 8 


Mar. 10, 


1885. 


J. Davis, 


Allegheny, Pa. 


313.542 


Mar. 10, 


1885. 


L. Simpson, 


Pittsburg, Pa. 


313.543 


Mar. 10, 


1885. 


Simpson and Davis, 


Pittsburg, Pa. 


3H.I99 


Mar. 17, 


1885. 


L. Simpson, 


Pittsburg, Pa. 


314,200 


" 


" 


" 


a 


385.644 


July 3, 


1888. 


W. Schweickhardt, 


St. Louis, Mo. 


421,249 


Feb. 11, 


1890. 


A.J. Darragh, 


Allegheny City, Pa. 


461,019 


Oct. 13, 


1 891. 


G. Hulseman, 


Cincinnati, 0. 


497.95 1 


May 23, 


1893. 


J. Davis, 


Allegheny City, Pa. 






Hides, Skins and Leather. 




No. 


Date 




Inventor. 


Residence. 


343.247 


Aug. 6, 


1886. 


E. B. Light, 


Denver, Col. 


363.546 


May 24, 


1887. 


C. A. Schieren, 


Brooklyn, N. Y. 


381,932 


May 1, 


1888. 


C. M. Kimball, 


Haverhill, Mass. 


381,933 


a 


ti 


" 


a 


393.845 


Dec. 4, 


1888. 


G. P. McMahon, 


Pawtucket, R. I. 


400,443 


April 1 2, 


1889. 


C. W. Cooper, 


Brooklyn, N.Y. 


408,896 


Aug. 13, 


1889. 


P. Latulip, 


Syracuse, N. Y. 


451,796 


May 5, 


1891. 


G. W. Baker, 


Wilmington, Del. 


478,499 


July 5. 


1892. 


T. Burns, 


Edinburgh, Scotland 


487,067 


Nov. 29, 


1892. 


J. W. Deckert, 


Newark, N. J. 


578,257 


Mar. 2, 


1897. 


McKenzie and Shaw, 


Cheboygan, Mich. 






Leather Working Machinery . 




No. 


Date 




Inventor. 


Residence. 


294,320 


Feb. 26, 


1884. 


J. Ff. Hovey, 


Woburn, Mass. 


294,394 


Mar. 4, 


1884. 


R. H. Lufkin, 


Chelsea, Mass. 


297,260 


Apr. 22, 


1884. 


A. Heim, 


New York City. 



APPENDIX. 



653 



No. 
300,812 
328,078 

342,193 
370,068 
386,187 
388,419 

392,"3 
402,060 
402,061 
402,062 
402,069 
404,904 

425,935 
43' .549 
43i>5 61 
453.HI 
579,468 



No. 

346,487 
361,176 

373,748 

427,555 
440,240 
444,724 
464,493 
470,872 
511,300 
5H>52I 



No. 
299,701 
310,279 
311,582 
323,334 
330,655 

335^97 
339,323 
341,977 
344,068 
344,069 
363,295 

373,ii2 
382,262 

383,9H 
401,905 
425,112 
456,421 
462,838 

44i,i73 
484,146 \ 
484,147) 



Date. 
June 24, 1 J 
Oct. 13, i{ 
May 18, li 
Sep. 20, 1$ 
June 17, if 
Aug. 28, ii 
Oct. 30, i{ 
Apr. 23, i! 



Apr. 23, 1889. 
June 11, 1889. 

Apr. 15, 1890. 
July 8, 1890. 
July 8, 1890. 
May 26, 1 89 1. 
June 23, 1897. 



Date. 
Aug. 3, 1886 
Apr. 12, 18 
Nov. 22, 1887 
May 13, 1890 
Nov. 1 1 , 1 890 
Jan. 13, 1 891 
Dec. 8, 1891 
Mar. 15, 1892 
Dec. 19. 1893 
Dec. 26, 1893 



Date. 
June 3, 1884 
Jan. 6, 1885 
Feb. 3, 1885 
July 28, 1885 
Nov. 17, 1885 
Feb. 2, 1886 
April 6, 1886 
May 8, 1886 
June 22, 1886 

it a 

May 17, 1887 

Nov. 15, 1887 
May 1, 1888 
June 5, 1888 
April 23, 1889 
April 8, 1890 
July 21, 1891 
Nov. 10, 1 89 1 
Jan. 6, 1 89 1 

Oct. 11, 1892. 



Inventor. 
S. S. Spear, 
A. F. Stowe, 

C. S. Fifield, 
F. Knox, 

J. J. and G. J. Daley, 

D. Knox, 

W. Foglesong, 
M. Brock, 



J. A. Crosbie, 

C. S. Gooding and S. 

W. Ladd, 
F. Bain, 
M. Brock, 
J. A. Crosbie, 
M. Brock, 
F. J. Bringham, 

Tanners' Tools. 

Inventor. 

A. V. Manly, 
J. McDermott, 

P. S. Connor, 
R. H. Houk, 
H. B. Bryant, 
H. L. Clark, 

B. Schnepp, 
W. F. Lawley, 
O. Geisler, 

Helical Tools. 

Inventor. 
J. W. Vaughn, 
W. M. Hoffman, 
J. Hodskinson, 
W. M. Hoffman, 
A. E. Whitney, 
W. M. Hoffman, 
J. Rood, 
A. E. Whitney, 
J. W. Vaughn, 

Lichtenburg and Ba- 

louin, 
J. W. Vaughn, 
J. Hodskinson, 
Rood and Vaughn, 
J. Rood, 
J. Straiton, 
M. and V. Martin, 
W. Evans, 
J. W. Vaughn, 

W. Evans, 



Residence. 
South Weymouth,Mass. 
Worcester, Mass. 
Revere, Mass. 
Boston, Mass. 
Brooklyn, N. Y. 
Lynn, Mass. 
Dayton, O. 
Boston, Mass. 



Methuen, Mass. 

Brookline, Mass. 
Chicago, 111. 
Boston, Mass. 
Methuen, Mass. 
Boston, Mass. 
Chicago, 111. 



Residence. 
Norwich, N. Y. 
Middletown, N. Y. 

Lake, 111. 
Morris, 111. 
Manchester, N. H. 
Canton, Pa. 
Louisville, Ky. 
Kennedy, Ala. 
Gloversville, N. Y. 



Residence. 
Peabody, Mass. 
Buffalo, N. Y. 
Salem, Mass. 
Buffalo, N. Y. 
Winchester, Mass. 
Buffalo, N. Y. 
Salem, Mass. 
Winchester, Mass. 
Peabody, Mass. 



Milwaukee, Wis. 
Peabody, Mass. 
Salem, Mass. 
Salem, Mass. 
Salem, Mass. 
Bootle, England. 
Paris, France. 
Philadelphia, Pa. 
Peabody, Mass. 

Philadelphia, Pa. 



654 




APPENDIX. 




No. 


Date. 


Inventor. 


Residence. 


467,216 


Jan. 19, 1892. 


A. E. Whitney, 


Winchester, Mass 


473.039 


it it 


a a 


a a 


494,183 


Mar. 28, 1893. 


" " 


tt a 


497,941 


May 23, 1893. 


G. W. Baker, 


Wilmington, Del. 


5°9,5°3 


Nov. 28, 1893. 


A. E. Whitney, 


Winchester, Mass 


512,088 


Jan. 2, 1894. 


G. W. Baker, 


Wilmington, Del. 


525,052 


Aug. 28, 1894. 


E. T. Marble, 


Worcester, Mass. 


526,387 


Sept. 25, 1894. 


W. Evans, 


Philadelphia, Pa. 


526,724 


Oct. 2, 1894. 


C. J. Mayer, 


Lynn, Mass. 


528,638 


Nov. 6, 1894. 


G. A. Lawrence, 


Peabody, Mass. 


535,777 


Mar. 12, 1895. 


J. Vaughn, 


Salem, Mass. 


537,254 


April 9, 1895. 


it 


a a 


539,io4 


May 14, 1895. 


(i 


tt a 


546,868 


Sept. 21, 1895. 


a 


a tt 


538,944 


May 7, 1895. 


G. W. Baker, 


Wilmington, Del. 


540,337 


June 4, 1895. 


A. Seymour-Jones, 


Wrexham, Eng. 


541,262 


June 18, 1895. 


J. Boyle, 


Peabody, Mass. 


547,984 


Oct. 15, 1895. 


tt 


" " 


552,628 


Jan. 7, 1896. 


A. E. Whitney, 


Winchester, Mass 


552,791 


Jan. 7, 1896. 


R. Steyer, 


Dohna, Germany. 


55^,813 


Mar. 24, 1896. 


W. Evans, 


Philadelphia, Pa. 


569,136 


Oct. 6, 1896. 


A. F. Jones, 


Salem, Mass. 


570,653 


Nov. 3, 1896. 


A. E. Whitney, 


Winchester, Mass. 


572,532 


Dec. 8, 1896. 


W. Evans, 


Philadelphia, Pa. 


572,533 


it a 


" 


it tt 


578,309 


Mar. 9, 1897. 


G. W. Baker, 


Wilmington, Del. 


583,995 


June 8, 1897. 


J. Hall, 


Leeds, Eng. 


587,717 


Aug. 10, 1897. 


W. Evans, 


Philadelphia, Pa. 



A copy of any one of these patents can be obtained by sending to 
the Commissioner of Patents, Washington, D. C, one coupon order 
properly filled out. These coupons cost 10 cents each, in large or 
small quantities. 



INDEX. 



ABATING, 153 
Acacia Arabica bark, 401 
Acetic acid, plumping by means of, 
177, 178 
and lactic acids, mixture of, for 
bating purposes, 156, 157 
Acid liquors, substitution of, for lime, 

90 
Acids, swelling effect of, upon the 
skin fibres, 28 
use of, as bates, 164 

for toning down, 539 
Ackerman & Brummel's cut sole 

factory, 388, 389 
Aesculotannic acid, 45 
Albumin, patent, 613 
Alder bark, 46 

Alizarine colors, fixing of, on chrome- 
tanned leather, 558 
list of, 566, 567 
dyes, 323 

dyeing leather with, 324, 325 
red on leather, 556 
Alligator leather, 466-469 

skin, japaned leather in imita- 
tion of, 453, 454 
skins, trade in, 467, 468 

treatment of, 468, 469 
Alum, 283, 284 

concentrated, 283 
use of, as a bate, 164 
Alumina, sulphate of, 561 
Aluminium acetate, 284, 285 

hypochlorite, bleaching with, 536 
sulphate, 282, 283 

containing free sulphuric 
acid, preparation of, for 
tanning purposes, 283 
detection of free sulphuric 

acid in, 283 
neutral, preparation of, 282 
American degras from wool waste, 
631, 632 
hemlock extract, 34 
hyposulphite of soda, 287 
Oak Leather Co., lay-away vats 
of the, 383 
leaching sys- 
tem in use 
by the, 58 

(655) 



American process of oil-dressing 
skins, 232. 233 
sumach, 32 

Tool & Machine Co., belt knife 
leather splitting machine man- 
ufactured by the, 194-198 
Ammonia alum, 283 

carbonate, use of, as a bate, 164 
muriate of, use of, as a bate, 164 
Anderson, Wm., on depilating with 

charcoal, 114 
Angora goat, intense black for, 498 
Aniline colors, adaptability of, for 
leather dyeing, 553 
application of, 554 
dyeing power of, 603 
list of, 566, 567 
most important, 583 
practical dyeing with, 564- 

566 
samples of leather dved 

with, 564-566 
solutions of, 554 
Animal skin, 21-28 

structure of the, 21 
Anthrax, 629, 680 

Argentine Republic, exports of que- 
bracho from, 40 
forests of quebracho 
trees in, 40, 41 
Arsenic and lime, active depilatory 
agent of the mix- 
ture of, 108, 109 
explanation of the 
depilatory power of 
the mixture of, 109 
-lime paste, preparation of, 103 
limes, 335 

red, part played by, in the mix- 
ture of it with lime, 118, 119 
proximate analysis of, 118 
results obtained by, 111 
use of, in liming, 93 
Artificial fur, beaver and nutria, im- 
provements relating to the manu- 
facture of, 500 
Ash gray, light, on glace" leather, 607 
Atmospheric pumps, 13, 14 
Australia, tanned sheep-skins from, 
571 



6^6 



INDEX. 



Austria, Russia leather manufactured 

in, 478 
Avellis, E., and Koster, E., patent of. 

for preparing chrome-tanned 

leathers for dyeing, 322 
Avens root, 47 

BABUL bark, -101 
Back- boarding, 373 
Bacteria pilline, 120 
Bag, case, welt, pocket book and strap 
leather, and flexible splits, to 
dress, 037, 6S8 
leather, 414 
Bank oil, tanning principle of, 234 

straits or menhaden oil, 228, 229 
Barbeny yellow on leather, 557 
Barium chromate, 286 

sulphide, depilating with, 1 14—1 1 G 
Bark business, fads in the, 64 
conveyer, 68-71 

cutter, automatic knife grinder 
for, 68 
made by the Vaughn Ma- 
chine Co., 66, 67 
grinding of, 59, 60 
loss in tanning substance of, in 

layaways, 57 
mills, 63-68 

various constructions of, 66 
shaving of, 181 
Barkometer, the, 62 
Bartenbach and Richter's quick tan- 
ning process for lace and whip 
leather, 546. 547 
Bases, most important, 554 
Bassett belt knife splitting machine, 

202. 203 
Batchelder's leather blacking, color- 
ing and dressing machine, 257-262 
Bate, bran, 155 
coal tar, 156 
for goat skins, 377, 378 

hides for upper leather, 140 
sole leather, 160, 161 
liquor, England wheels for agi- 
tating, 166 
manure, danger of. 154 
Bates, substitutes for, 155 

various, 164 
Bath, definition of a, 339 

green, 616 
Bating, 88, 153-166 

and washing, vats and wheels for, 

165 
compounds, 509 

economies and improvements in, 
93 



Bating, method of, 157 

present method of, objections to, 

164 
purpose of, 94 
usual process of, 164-166 
Beam and stand, German form of, 130 
-face, glass, 301 
house, greatest risk in the, 153 

interior view of the, 130 
used in currying shops, 250 
Beech bark, 46 

Beecher system of grinding bark, 64 
Beggs & Cobb, system of leaching 

hemlock bark used by, 58 
Belt knife splitting machine, 188, 194- 
198 
improvement 
on grinder 

rigging for . 
201, 202 
machines, Robert- 
son's grinding 
adjustment for, 
203-207 
leather, machine, greased with 
tallow, 405, 406 
wet stretching machine for, 
409-411 
straps, leather for, 415 
Belts, engine, currying strap butts 

for, 407, 408 
Belting and harness leather, 390-411 
for lighter purposes, 391, 392 
leather, hides used for, 390 

to remove grease from, 408, 
409 
Bichrome, 330 
Bichromate, 330 
Bichromates, first use of, for tanning, 

289 
Bicycle seats, leather for, 414 
Binders, skivers and lining, 512, 513 
Birch oil and leather, 486, 487 
manufacture of, 484-486 
Payen's apparatus for distill- 
ing, 486 
products of the distillation of, 
. 486 

Russian method of distilling, 

486,487 

preparing, 

478, 479 

tar, 487 

and pine tar, differentiation of, 

488 
oil, 487 
Black buffings, plain, 449 

colored Russia leather, 484 



INDEX. 



657 



Black deep nigrosin, 612 
dyeing leather, 609, 610 
enameled top leather, 444-447 
intense dull, on bark-tanned 

sheep-skins, 525 
leather, to put a gloss on, 505, 

506 
"Norris, " 374 
on cordovan leather, 581 

genuine Russia leather, 580 
glove skins, 503, 504 
morocco leather, 581 
rabbit skins, 616 
tawed leather, 582 
spots, 121 

varnish, preparation of, 448 
Blacking brushes, 256 
for splits, 427 

grain and split leather, 424 
leather, 256-262 
Bleaching chamber, 533, 534 
chamois leather, 536 
heavy leather, 537, 538 
leather, 532-538 

bluing white leather, bleach- 
ing skins with the hair on, 
532-541 
skins with the hair on, 540, 541 
with aluminium hypochlorite, 536 
hydrogen peroxide, 535 
magnesium hypochlorite, 

536 
potassium permanganate, 

536 
sodium peroxide, 535 
solution of sulphurous acid, 

534, 535 
sulphurous acid, 532-534 
Bleeding or smutting off of colors, 

563, 564 
Blended colors upon glace" leather, 

directions for, 604-608 
Blue-black liquor for finishing, 432 
nigrosiu color, 612 
tinge with ursol colors, 498, 
499 
-bluish on sheep-skins, 522 
on morocco leather, 581 

tawed leather, 582 
-reddish on sheep-skins, 522 
Bluing white leather, 536, 537 
Blumenthal, F. & Co., plans of the 

kid factory of, 361-363 
Board, dyeing upon the, 601-603 
Bolton planimeter, 281 
Bony fish, 228 

Book bindings, leather for, 414, 415 
Boracic acid, use of, for bating, 158 
42 



Borax, 242, 622-628 
for bating, 158 

preserving hides, 381, 623 
purifying water, 10, 11 
softening water, 83, 594, 622. 
623 
in quick tanning, 52 
Bordier, patent obtained by, for tan- 
ning with ferric sulphate, 287 
Borol, 157 
Botchford, H. J., distillation of sour 

liquors proposed by, 174, 175 
Bowers rocker-motion leather finish- 
ing machine, 263-265 
Boyden, Seth, invention of a splitting 

machine by, 186 
Bran bate, 155 

drench, 336 
Brazil, alligator skins from, 467 
Breaking, fleshing, unhairing and 

slating machine, 331, 333 
Brown, chestnut, on leather, 556 
chocolate, on leather, 556 
colors for, 572, 573 
cutch, 011 leather, 556 
dark, bister, on glace leather, 
605 
on leather, 555, 556 
glace leather, 606 
light, on leather, 556 
olive, on leather, 556 
on morocco leather, 581 

tawed leather, 582 
pure Havana, on glace leather, 

605 
Sienna, on glace leather, 605 
wood, to mahogany color on 
glace leather, 605 
Brownish red, on glace" leather, 605 
Brush, scouring, 208 
Brushed kid, finishing of, 368 

seasoning for, 368 
Brushes, blacking, 256 
Bublah, 33 

Buenos Ayres, process for using pure 
quebracho wood for sole leather in, 
41, 42 
Buff hides, 41W 
Buffed leather, 432, 433 
Buffing and whitening machine, 

Union, 251-254 
Buffings for japanning, classes of, 444 

plain black, 449 
Buggy tops, black enameled leather 

for, 444-447 
Bull, A., patent for a bark mill re- 
ceived by, 64 
Bull's leather, bleaching of, 537, 538 



658 



INDEX. 



Burns, Peter S., and Hull, Chas. S., 
invention of, 156 

CALCIUM bichromate, 286 
thioarsenite, depilatory prop- 
erties of, 119, 120 
Calf, Dongola, 375, 376 
kid, best bate for, 158 

soaking of, 84 
leather dyeing, 569-571 

list of dyes for, 570, 571 
Russia odor to, 488 
or goat skins, tanning of, by the 

chrome process, 304-306 
Russia, 470-474 

coloring of, 473, 474 
waxed, quality of the water in 
the manufacture of, 18 
temperature of the water in 
the manufacture of, 15 
Calfskin, reduction of, 161 
Calfskins, chrome-tanned, correct ox- 
blood shade on, directions for, 
• 573, 574 
combination tan or straight gam- 
bier tanned, formula for cor- 
rect ox-blood shade on, 567, 568 
dyeing of, for shoe work, 572, 573 
French process of unhairing and 

finishing, 133-135 
in the hair, tanning of, 491, 492 
mixed depilatory for, 98 
paste for, 427 

tanned, preparation of, for dye- 
ing, 571, 572 
treatment of, in the limes, 90 
Canaigre, 35, 36 
Cape sheep, 512 
Caracal, 373 

Carbolic acid, use of, as a bate, 164 
Carbonic acid in water, recognition 

of, 5 
Card, leather, splitting of, 416 
Carriages, large hides and sides of 
patent and enameled leather for, 
392 
Carriage tops, black enameled leather 
for, 444-447 
hides for, 436 
Case, welt, strap, pocket book and 
bag leather, and flexible splits, to 
dress, 637, 638 
Castile soap, 555 
Catechu, 29, 30 
Cavalin, first use of bichromates for 

tanning by, 289 
Cawnpur hides, results of tests of, 
404, 405 



Cawnpur, India, system of tannage 

used in the factory at, 401-403 
Chamois leather, bleaching of, 536 
color of, 532 

mixtures for, 581 I 
imitation, 510, 511 
Charcoal, depilating with, 113, 114 
Chebog, 228 

Chemistry in tanning, 154 
Chestnut brown on leather, 556 

oak bark liquor, tanning sub- 
stance contained in, 385 
tree, manufacture of tanning 

extract from the, 74-76 
wood, 45 
tree, manufacture of tanning ex- 
tract from the, 74-76 
Chicago, sheep received in, 507 
Chinese gall nuts, 31 
Chloride of potash, 355 
Chlorine combinations in water, de- 
termination of, 4 
Chocolate brown on leather, 556 
Chromates, neutral, 286 

quick tanning with, Heinzerling's 
process for, 293-296 
Chrome bath, reactions occurring in 
the preparation of the, 
352 
Schultz's directions for the 
preparation of the, 351 
goods, solution to prevent com- 
plete drying out of, 356 
introduction of, 326 
leather, characteristics of, 319-321 
currying of, 321 
fat liquor for, 321 
leathers, dyeing of, 323-325 
or mineral tannage, 289-304 
process, tanning calf or goat 
skins by the, 304- 
306 
sheep-skins by the, 
306 
tannage, central idea of methods 
of, 314 
competition of, with bark, 302 
increase in, 301 
kangaroo, finishing of, 425 
some patents for, 306-308 
two-bath method, tan vat 
used in the, 343 
-tanned calf-skins, correct ox- 
blood shade on, directions 
for, 573, 574 
horse hide butts, wax finish 

on, 464 
kid, qualities of, 326 



INDEX. 



659 



Chrome-tanned leather, chromol fat 
liquors for, 244 
fixing of alizarine 

colors on, 558 
method of color- 
ing, 617, 618 
qualities of, 301 , 

302, 328 
Wm. M. Norris on, 
328-330 
leathers, preparation of, for 
dyeing, 322 
tanning and German tanners, 307 

methods now in use, 297 
upper leather, 301 
yellow on leather, 557 
Chromic acid, deterioration of leather 
made by the use of, 315 
alum, 314 

oxide, properties of, 313 
Chromium alum, 283, 284, 286 

preparation of the salt of, used 
in the Dennis process, 315, 316 
salts, 285, 286 
sulphate, 286 
Chromol fat liquor for chrome-tanned 

leather, 244 
Claret or maroon on sheep-skins, 524 
Clark's process of determining the 

hardness of water, 5-9 
Coal tar bate, 156 
Cochineal on sheep-skins, 523 
Cod fishery, chief seat of, 224 
oil, 223-225 

adulterations of, 225 
classification of, 224 
manufacture of, 224 
properties of, 224 
substitutes for, 225 
tanning principle of, 234, 235 
value of, as a leather lubricant, 
235 
Cold sweat process, 121 

tan process for fur skins, 494 
Color, depth of a, dependent on the 
quantity of mordant, 575 
facilitating evenness of, 562 
• imparting a light, to leather, 538- 
540 
mixtures, 580-584 
production of a definite tone of, 

575-577 
scale, use of a, 577, 578 
uniform, hints to obtain a, 553 
tanners' preparation for ob- 
taining a, 562, 563 
Coloring chrome-tanned leather, 
method of, 617, 618 



Coloring kid, 374, 375 

matter, fixation of, by a mordant, 

574, 575 
morocco, 374, 375 
Wm. M. Norris on, 374, 375 
Colors, aniline, dyeing power of, 603 
list of, 566, 567 
practical dyeing with, 564- 

566 
samples of leather dyed 
with, 564-566 
alizarine, list of, 566, 567 
bleeding of, 563, 564 
blended, 584 

upon glace" leather, direc- 
tions for, 604-608 
broken, toning fluids for, 607, 

608 
for brown, 572, 573 
Russia calf, 474 
mixed, 608, 609 
smutting off of, 563, 564 
waterproof, 560, 561 
Combination tan or straight gambier 
tanned calf-skins, formula for cor- 
rect ox-blood shade on, 567, 568' 
Common salt, 288, 289 
Compigne, Dr., analysis of water from 

Ganges Canal by, 401 
Compo, 463 

Connective tissue substance, formula 
of, 28_ 
preparation of, 

27 
properties of, 
27 
Coombs pendulum jack, 271, 272 
Creme of logwood, 559, 560 
Crimping splits, finishing of, 425, 426 
Copper, sulphate of, 561 
Cordovan, 462-464 

leather, color mixtures for, 581 
sorting of, for dyeing, 585 
Coriln, 22 

formula of, 27 
preparation of, 25 
properties of, 26 
Corium, the, 21, 22 
Cottle & Son, system of leaching 

hemlock bark used by, 58 
Counter-fleshing, 138 
Counters, 389 

Coupe's stretching machine, 547-549 
Cow hides, soaking of, 78 
Curriers' knives, 250, 251 
oils and grease, 221-228 
skirting, 395 
Currying chrome leather, 321 



66o 



INDEX. 



Currying harness leather, 392-395 
Indian harness leather, 403, 404 
shops, beam used in, 250 
location of, 1 
modern, fitting up of, 530 
strap butts for mill bands and 
engine belts, 407, 408 
Cut sole factory, Ackerman & Brum- 
mel's, 388, 389 
soles, 387-389 

oak-tanned sole leather, un- 
scoured and scoured leather, 
379-389 
Cutch brown on leather, 556 

DAGGEAT, 479 
Danish leather, 412, 413 
D'Arcet, tanning with ferric salts re- 
commended by, 287 
Dark bister brown on glace leather, 605 
brown on glace leather, 606 
leather, 555, 556 
gold ochre to umber on glace 

leather, 605 
green on leather, 557 
pigeon gray on glace leather, 606 
Daub, application of, 446 
for regalia leather, 450 
preparation of, 444, 445 
Deep black nigrosin color, 612 
Deer-skins, furs and peltries, tanning 

of, 493, 494 
Degras, 226, 230-235, 435, 630, 631 
American from wool waste, 631, 

632 
artificial, 238. 239 
French, 227 

early use of, 231 
production of, 232 
mixture of, 230 
per cent of water in, 632, 633 
preparation of, 230 
Vickers', 231 
Degreasing liquid, 496 
Deliming, chemical, 335 
Denmark, origin of the manufacture 

of horse leather in, 461 
Dennis Chrome Tannage Co., direc- 
tions by the, for 
tanning sheep- 
skins, 306 
directions by the, 
for using tanolin 
on calf or goat- 
skins, 304-306 
new form of sodium 
sulphide intro- 
duced by the, 99 



Dennis method of tanning, 298-300 
one-bath process, 297 

advantages of, 307 
process of tanningleather,313-319 
tanning liquor, 308-313 
Depilating by sweating, 120, 121 
with charcoal, 113, 114 

sodium sulphide, 97-113 
sulphide of barium, 114-116 
Depilation, methods for accomplish- 
ing, 86 
or unhairing, 86-129 
Depilatories, alkaline, necessity of 
the removal of, from hides 
and skins, 155 
chemistry of, 116-120 
Depilatory, definition of a, 86 
Dimitry's method of preparing water- 
proof colors, 560, 561 
Dipping apparatus, 599, 600 

process of dyeing, 598-600 
Dizer, M. C, & Co., experiments in 

quick tannage by, 527 
Dog-pure, 94 

preparation of, 163 
Dongola, blacking of, 424 
calf, 375, 376 

old process of converting goat- 
skins into, 376-378 
stuffing for, 424 
Dow & Co., system of leaching hem- 
lock bark used by, 58 
Drenching, 153 
Dressing sheep-skin fleshers for glove 

bindings, 513, 518, 519 
Drying loft for sole leather, tempera- 
ture of, 385 
in a morocco factory, 364, 
365, 369, 370 
sheep-skin tannery, 
513, 516 
oven in a patent leather factory, 

447 
yard of an upper leather tannery, 
422, 423 
Drum, heating the, 216, 217 

revolving, for handling, 172 
stuffing, 216-218 

Freeman's, 221 
tannage, 399, 400 
treating skins in a, 337 
Drums, tramping, improvement in, 

220, 221 
Dung-bating, theory of, 163, 164 
Durio, F., process of quick tannage, 

527 
Duval-Duval's method of distilling 
birch oil, 485 



INDEX. 



66 1 



Dye bath, dilution of the, 577 

preparation of the, 574-578 
-stuffs, crankisms of, 553 
selection of, 588 
reacly-made, working with, 578 
Dyeing and tanning furs and hair 
skins, 491-500 
alizarine red, 556 
Angora goat, 498 
barberry yellow, 557 
bark-tanned sheep-skins intense 

dull black, 525 
board, the, 601 
calf leather, 569-571 

-skins for shoe work, 572, 
573 
chestnut brown, 556 
chocolate brown, 556 
chrome leathers, 323-325 

yellow, 557 
Continental method of, 558 
cutch brown, 556 
dark brown, 555, 556 

green, 557 
dipping apparatus for, 599, 600 

process of, 598-600 
English method of, 558 
fluids, arrangement of the, 601 
fur skins, 494-500 
glace leather, 598 
goat-skins, 497 

imitation nutria in clipped rabbit, 
498 
seal skin in clipped musk- 
ox, 498 
leather, 553-616 
black, 609, 610 
for shoes, 571-573 
methods of, used in Germany, 

574-616 
with the alizarines, 324, 325 
lemon yellow, 557 
light brown, 556 

olive green, 557 
long-haired musk-ox, 498 
mode of, 557 
most important bases and salts 

used in, 554, 555 
one-tray process of, 558 
olive brown, 556 
operation of, 601-603 
orange, 557 
ordinary red, 557 
paddle method of, 558 
picric green, 557 
practical, appliances required for, 

499, 500 
precautions in, 560 



Dyeing, preparation of chrome-tanned 
leathers for, 322 
leather for, 584 
tanned calf-skins 
for, 571,572 
rabbit skins, 497 

black, 616 
red, 556 

russet leather, 417 
Russia leather red, 481 
scarlet. 556, 557 
sheep-skins, 522-525 
sorting leather for, 585, 586 
table, the, 601 
tawed leather, 598 
Thibet, 497 

two-tray process of, 558 
upon the board, 601-603 
utensils required for, 601 
various methods of, 557, 558 
washing the skins for, 586-588 
wild goat, 497, 498 
with logwood and potassium 
chromate, 610, 611 
mineral colors, 608, 609 
tannin and iron salts, 610 
logwood, 611 
Dyes and toning fluids, 603, 604 
for calf leather, list of, 570, 571 
colors of a pure tone, 604 
glace leather, 604 
wood, advantage of, 558 

EAST Indian kino, 29 
r Eitner, Prof., method for employ- 
ing quebracho with 
oak bark for sole 
leather recommend- 
ed by, 42, 43 
on the uses of que- 
bracho, 38, 39 
Egg, yolk of, preservation of, 597 
Electric and other rapid tannage sys- 
tems, 526-531 
transmission of power, 636, 637 
Elm bark, 45 

Enamel, horse hides for, 464, 465 
Enameled leather, patent leather, 
furniture or up- 
holstering leather, 
regalia leather, 436- 
460 
stuck together, a good 

way to open, 451 
stuffing for, 440, 441 
or japanned leather, preparing 
the cut surface of split leather 
for manufacturing, 452, 453 



662 



INDEX. 



Enameled varnish, 446 

Engine belts, currying strap butts for, 

407, 408 
England, L. C. , apparatus invented 

by, 168-170 
England wheel, bating in the, 420 
wheels for agitating bate liquor, 
166 
English crown leather, grain of, 418, 
419 
sod oil, 226, 227 
Enos, John A., attachment to the 
Union splitting machine, patented 
by, 188, 190-192 _ 
Epidermis, composition of the, 21 

nature of, 112 
European galls, 30, 31 

FAHR, George, discovery of the 
tanning properties of quebracho 
by, 37 
Fat liquor, chromol, for chrome- 
tanned leather, 244 
for chrome leather, 321 
formula for making, with 

Palermo fig soap, 243 
use of degras as, 231 
liquoring with Palermo fig soap, 

242, 243 
liquors, 243, 244 
Fats, most common and abundant, 
223 
properties of, 222 
Fawn, production of modification 

with, 575 
Ferric salts, 287, 288 

Knapp's method of prepar- 
ing, 292 
patent for tanning with, 
290-292 
sulphate, basic, preparation of, 290 
preparation of, 287, 288 
Ferrocyanide of potassium, 561 
Fiebing, Prof., on the use of sodium 

sulphide for depilating, 97, 98 
"Fine hair," 109 

hairing, best time for, 158 
Finish, bright, for glove grain, 430, 
431 
coat for flesh splits, 430 
for imitation goat grain, 431 
kangaroo, 431 
pebble grain, 431 
satin oil leather, 431 
gum tragacanth, 426, 427 
Finishing and pebbling machine, 
Knox improved inclined bed, 
268-271 



Finishing blue black liquor for, 432 
furniture leather, 449 
machine, Bowers rocker-motion, 
263-265 
Martin's improved, 267, 
268' 
polishing or glassing, pebbling, 
rolling, etc., machines for, 263- 
272 
room, the, 450 

in a sheep-skin tannery, 513, 
517 
skirting, 395 
upholstering leather, 449 
varnish for smooth finished 
patent leather, 449 
Fir bark, 34 
Fischerstroem's method of distilling 

birch oil, 485 
Fish oil, conversion of, to sod oil, by 
oxidation, 234 
value of, as a leather lubricant, 
235 
Flanders, Jos. F., and Marden, Jere 
M., invention of the belt splitting 
machine by, 188 
Flesh splits, 429-432 

finish coat for, 430 
stuffing for, 429 
Flesher, saw-toothed, 136 
Fleshers, spring, 136 
Fleshing and unhairing by hand and 
machinery, 
130-152 
by machinery, 

140-152 
machin es, 
pra ctical 
success of, 
151 
by the hand method, 135-138 
green, 379 

how long should the hides soak 
after, and what indicates their 
readiness for scouring, 139, 140 
knife, 135, 136 
Flexible splits, 433-435 

to dress, 637, 638 
Float for whole hides, 184 
Foederer, R. H., first production of 
commercial leather tanned by 
Schultz's process by, 298 
Foley, process for treating hides and 
skins previous to tanning invented 
by, 114-116 
Forbes, Prof. , on the value of canaigre 

tanning materials, 36 
Forster's sandstone filter, 594, 595 



INDEX. 



66 3 



Foss, C, earliest patent for a bark 

mill awarded to, 63, 64 
Frame for stretching leather, 441-443 
Frames for japanning side leather, 
444 
hide, 444 
split, 444 
France, process of unhairing and 

finishing calfskins in, 133-135 
Freeman & Co., improved iron glass- 
ing jack made 
by, 266 
straight bed roll- 
ing or peb- 
bling jack 
made by, 266, 
267 
stoning jack made by, 

185, 415 
stuffing drum, 221 
Union whitening and 
buffing machine 
made by, 251-254 
French degras, 227 

early use of, 231 
production of, 232 
kid, imitation, finishing of, 366- 
368 _ 
selection of skins for, 
368 
method for tanning oil-dressed 

leather, 232 
moellon oil, 227 
sumach, 32 
whitening slicker, 250 
Frieze, 121 

Fur, artificial, beaver and nutria, im- 
provements relating to the 
manufacture of, 500 
skins, cold tan process for, 494 
mordants for, 496 
Furniture or upholstering leather, fin- 
ishing of, 449 
leather, regalia 
leather, enam- 
eled leather, 
patent leather, 
436-460 
Furs and hair-skins, tanning and 
dyeing of, 491-500 
peltries and deer-skins, tanning 
of, 493, 494 
Fustic, 33, 34 
young, 559 

GALL nuts, 30, 31 
Galls, 31 
Gambier, 29 



Ganges Canal, analysis of water from 

the, 401 
Geranium wallachianum, 47 
German fleshing knife, 135, 136 

harness leather, 395-397 
Germany, methods of dyeing leather 

used in, 574-616 
Gift, 109 

Gilbert Bros. & Co., tanners' prepar- 
ation, prepared by, 562, 563 
Glace leather, blended colors upon, 
directions for, 604-608 
dyeing of, 598 
dyes for, 604 
nourishment for, 596 
sorting of, for dyeing, 585 
washing tawed skins for, 
586, 587 
Glassing jack, improved iron, 266 
or polishing, finishing, rolling, 
pebbling, etc., machines for, 
263-272 
Glazing and glassing of leather, 612- 
615 
fluid, preparation of, 612, 613 
leather, 612, 613 
machine, 263 
rolls, 615 
Gloss, to put a, on black leather, 

505, 506 
' Glossing and glazing of leather, 612- 
615 
apparatus, 614, 615 
leather, 614, 615 
mass, 614 
Glove bindings, dressing sheep-skin 
fleshers for, 513, 518, 519 
grain, blacking of, 424 

bright finish for, 430, 431 

finishing of, 425 
stuffing for, 422. 424 
kid, alum tawed, aging of, 106, 
107 
effect of sodium sulphide on, 

106 
reasons why sodium sulphide 
should not be used for mak- 
ing, 107, 108 
leather, tawing, dyeing lamb and 

kid skins for, 501-504 
leathers, inability to get colors 

right in, 161 
sheep leather, natural tan, sample 

of, 565 
skins, black on, 503, 504 
Glue, conversion of the connective 

tissue fibres into, 23, 24 
Glycerine, 236-240 



664 



INDEX. 



Glycerine albuminous, 239 

combination of, with tannin, 239 
fixing of, in the leather, 239 
for nourishing, 596 

softening, 412, 413 
properties of, 237 
stuffing with, 239, 240 
use of, 238 
Goat, Angora, intense black for, 498 
grain, imitation, finish for, 431 
finishing of, 425 
stuffing for, 424 
India tanned, 364 
oil, finishing of, 373, 374 
or calf-skins, tanning of, by the 

chrome process, 304-306 
pebble-grain, finishing of, 373 
-skin, dyed sample of, 565, 56*6 
India tanned, dark green, 
dyed sample of, 

566 
dyed sample of, 
565 
-skins, arsenic in liming, 93 
bate for, 377, 378 
dyeing of, 497 

high-limed bating of, 157, 158 
imported from India, 364 
in the hair, bleaching of, 

540, 541 
liming of, 377 
mill for, 377 

mixed depilatory for, 98 
old process of converting, 
into Dongola and other 
fine leathers, 376-378 
preparing the, 330-336 
sumac tannage of, 378 
tawing of, 336-343 
straight-grained, finishing of, 368- 
373 
graining of, 371 
seasoning for, 369 
wild, dark brown for, 497 
gray brown for, 497, 498 
<iold ochre, dark, to umber on glace 

leather, 605 
Goodyrear counters, 389 

insoles, 389 
Gorsline's apparatus for handling, 

172,173 
Grain, the, 421 

and split leather, 418-435 
artificial, on hides, 452, 453 
false, uneven, prevention of, 418 
leather, handling of sides for, 172 
Grainering, 153 
Graining, 166, 380 



Graining board, 371 

machine, Towein's, 483 
straight-grained goat, 371 
Grass green on sheep skins, 523,°524 
Gravity system of leaching, 49 
Gray on tawed leather, 582 
Grease and oils, curriers', 221-228 
"Ideal," 228 

removal of, from leather belting, 
408,409 
Green bath, 616 

brown to dark brown on glace 

leather, 606 
dark, on leather, 557 
fleshing, 379 
galls, 30 

light olive, on leather, 557 
on morocco leather, 581 t 
picric, on leather, 557 
on tawed leather, 582 
Grinding adjustment, Robertson's,, 
for belt knife splitting machines, 
203-207 _ 
Grinder rigging for belt knife split- 
ting machines, improvement on; 
201,202 
Groth system of rapid tannage, 526 
Grouvelle's process of distilling birch 

oil, 485 
Gum tragacanth finish, 426, 427 

HAHN & STUMPF, wax finish on 
chrome-tanned horse-hide butts 
made by, 464 
Hair bulbs, 23 

primitive manner of removing, 89 
roots, 23 
sacs, 23 
Hairskins and furs, tanning and dye- 
ing of, 491-500 
Hamburg, manufacture of horse 

leather in, 462 
Hand method staking machine, 273, 
274 
reel, the, 168 
stuffing, 215, 216 
Handler vats, 421 
Handlers, 382 

liquors going on the hides in the, 
383 
Handling, 167-173 

and plumping, 167-178 
England's apparatus for, 168-170 
European methods of, 172 
Gorsline's apparatus for, 172, 173 
methods of, 167 
paddle wheels for, 170, 171 
revolving drum for, 172 



INDEX. 



665 



Hardness of water, degrees of, 9 

determination of, 5-9 
Harness and belting leather, 390-411 
large hides and sides of patent 
and enameled leather for, 392 
leather, brown, 393, 394 
currying of, 392-395 
drum tannage for, 399, 400 
German, 395-397 
hides used for, 390 
Indian, 400-405 

currying of, 403, 404 
tanning process for, 402, 

403 
tests of, 404, 405 
quick tanning process for, 

392 
requisite qualities of, 390 
Hart, R., process of, for dressing 

sheep-skin fleshers, 513, 518, 519 
Hauff, P., patent of, 157 
Havana brown, pure, on glace leather, 

605 
Heading, 181 

Heinzerling's process for quick tan- 
ning with chromates, 293-296 
Hemlock bark, 34 

system of leaching, 58 
extract, preparation of, 76 
Hestahl's process for dressing sheep- 
skins, 520, 521 
Hibbard's method for preparing and 

tanning sheep-skins, 520 
Hide, cleansing the, with borax, 52 
constitution of, 112 
frames, 444 
grain of the, 112 

green, object of applying a mel- 
low liquor to a, 57, 58 
mills, construction of, 84 
practice of reducing the, 161 
substance, necessity of removing 

a certain amount of, 105 
thoroughly tanned, test for a, 396 
Hides and skins, preparation of, for 
soaking, 79-81 
working out and un- 
hairing all kinds of, 
without limes, bate, 
drench or beaming, 
116 
artificial grain on, 452, 453 
borax for preserving, 381 
buff, 419 

buffing of, for japanning or enam- 
eling, 452 
dried, soaking of, 79 
dry, softening of, 84 



Hides, dry, softening of, for sole 
leather, 82 
final soaking of, before placing 

in the ooze, 166 
for belting leather, 390 
enameled leather, 436 

or patent leather, split- 
• ting of, 

439 
tanning of, 
439, 440 
furniture leather, 436 
grain and split leathers, 419 
harness leather, 390 
Indian harness leather, 401 
lace leathers, 542 
limed stock, preparation of, 

89 
patent leather, 436 
regalia leather, 450 
upholstering leather, 436 
upper leather, bate for, 140 
vache leather, 399 
fresh, sweating of, 128, 129 
green, for upper leather, lime for, 
399 
soaking of, 79 
hand-buffed, grades of, 443 
heavy, final step in the process 

of tanning, 181 
horse, treatment of, 461, 462 
indications of the readiness of, 

for scouring, 139, 140 
ledger account of, 382 
light, consequence of the use of 
too concentrated solutions 
of tannin for, 390 
soaking of, 84 
machine buffed, grades of, 444 
mechanical devices for stretch- 
ing, 543, 544 
native slaughtered, soaking of, 79 
or skins, art of tawing, 618-622 
building for sweating, 
121-124 
percentage of rough leather ob- 
tained from, 386 
plumping of, 3 
Russian method of freeing from 

lime, 478 

soaking of, after fleshing by the 

hand method, 138, 

139 

in a steeping cistern 

after fleshing, 139 

splitting of, for grain and split 

leather, 421 
South American, 379 



666 



INDEX. 



Hides, sweating of, care to be observed 
in, 124-127 
swelling influence of natural 

waters upon, 26 
swelling of, 3 

temperature of the water for pre- 
paring the, 4 
Texas, 379 
unhairing of, by the hand 

method, 130-135 
washing of, for enameled or pat- 
ent leather, 437 
whole, float for, 184 

jack for raising the, up in the 

lay away vats, 183 
splitting of, 188 
Hirschsohn's process of differentia- 
tion of birch tar and pine tar, 488 
Hog and seal, imitation, 427, 428 
Holbrook system of leaching, 51 
Horse-chestnut bark, 45, 46 
extract, 46 
hide butts, chrome-tanned, wax 

finish on, 464 
hides for enamel, 464, 465 
memel, 465 
plain enamel, 465 
shoe purposes, 462-464 
treatment of, 461, 462 
leather, 461-465 
Hydrochloric acid, use of, as a bate, 

164 
Hydrogen peroxide, bleaching with, 

535 
Hyposulphite of soda, 287 

action of muriatic 
acid upon, 355 
determination of 
the proper 
amount of acid 
to use in con- 
nection with, 
354 
and potassium bi- 
chromate, de- 
termination of 
the proper rela- 
tion between, 
354 

U TDEAIv" grease, 228 

X Illinois, varieties of leather pro- 
duced in, 419 
Imitation goat, blacking of, 424 
grain, finish for, 431 
finishing of, 425 
stuffing for, 424 
seal and hog, 427, 428 



India, goat skins imported from, 364 
harness leather, 400-405 

currying of, 403, 404 
new, tests of, 404, 405 
process of tanning, 
402, 403 
tanned goat, 364 

skin, dark green, dyed 

sample of, 566 
dyed sample of, 565 
Indigo carmine, 559 

dyeing power of, 603 
Ingersoll-Sergeant Drill Co., the 
Pohle system of raising water, in- 
troduced by the, 16 
Intercellular substance, 25 
Iron alum, 283, 284 

gray on glace leather, 607 
salts and tannin, dyeing with, 610 
soap, 288, 291 

violet on glace leather, 606 
Italian sumach, 31 
Itch, 95-97 
white, 96 

JACK, Coombs pendulum, 271, 272 
for raising whole hides up in the 
lay-away vats, 183 
glassing, improved iron, 266 
stoning, 185, 415 
straight bed rolling or pebbling, 
266, 267 
Japanned leather in imitation of alli- 
gator skin, 453, 454 
renewing the surface 
on, 451 
Japanned or enameled leather, pre- 
paring the cut surface of split 
leather, for manufacturing, 452, 453 
Japanning, buffings for, 444 

side leather, frames for, 444 
Jones' patent bark cutter, 66, 67 
Juften or Juchten, 475 
Junior's method of manufacturing 
lace leather, 545, 546 

KANGAROO chrome-tannage, fin- 
ishing of, 425 
finish, 431 
stuffing for, 424 
Kas, S,, on quick tannage, 527 
Kettles, steam jacket, 242 
Kid and lamb skins for glove leather, 
tawing, dveing of, 501-504 
brush, the, 368 
brushed, finishing of, 368 

seasoning for, 368 
chrome-tanned, qualities of, 326 



INDEX. 



667 



Kid, coloring of, 374, 375 
colors for, 5S3 
factory, F. Blumenthal & Co.'s., 

plans of the, 361-363 
imitation French, finishing of, 
366-368 
selection of skins 
for, 368 
leather, bluing of, 536, 537 
or morocco factory, lime vats in 
a, 331,332 
leathers, 326-378 
tanneries, breaking, fleshing, un- 
hairing and slating machine 
used in, 331, 333, 334 
tanners of Philadelphia, Penna., 
softening mill used by, 84, 85 
Kino, 29 
Klipsteiu & Co. on the qualities and 

use of quebracho, 39 
Kips for upper leather, lime for, 399 
Knapp, Prof., experiments of, in 
making leather without 
tanning elements, 179- 
181 
experiments of, in tan- 
ning with ferric salts, 
287, 288 
improvement in tramping 

drums by, 220, 221 
patent obtained by, for 
tanning with ferric salts, 
290-292 
Knife, fleshing, 135, 136 

grinder, automatic, for bark cut- 
ter, 68 
short hair, 133 
unhairing, 130 
Knives, currier's, 250, 251 
Kuoppern, 31 

Knox improved inclined bed leather 
finishing and pebbling machine, 
268-271 
Koechlin, H., and Knecht, B., pro- 
cess by, of dyeing leather with the 
alazarines, 324, 325 

LABARRAOUE'S solution, prepara- 
tion of, 540 
Lac brown on glace leather, 606 
Lace and whip leather, quick tanning 
process for, 546. 547 
leather, golden color on, 545 

Junior's method of manu- 
facturing, 545. 546 
Loescher's method for man- 
ufacturing, 547 
leathers, 542-552 



Lactic acid, 323 

plumping with, 178 
Lamb and kid skins for glove leather, 
tawing, dyeing of, 501-504 
-skins in the hair, bleaching of, 
540, 541 
Lang Co., Newark, N. J., Pohle air 
lift plant at the works of the, 19, 20 
Larch bark, 34 
Latches, Indian, 402 
Lay-away vats, 181,383 

jack for raising the whole 

hides up in the, 183 
liquors in the, 183 
yard, 383 
Layers, number of, 181, 182 
Laying away, 179-184 
Leach, head, general rule for the, 50 
ideal, 50, 51 

ledger account for each, 60 
limit to the length of the column 

of bark in a, 55 
pumps, 52 
Leaches, pumping of, 59 

tail, temperature of the water or 
liquor applied to the, 56 
Leaching, 48-62 

barkometer; bark mills; bark 

conveyer; the tan press, 48-73 
cardinal points to be considered 

in, 48 
check on the efficiency of, 56, 57 
difficulty experienced in, 53 
forced, systems of, 48 
gravity system of, 49 
Holbrook system of, 51 
illustration of the most common 

way of, 49 
most seriously defective system 

of, 51.52 
point of saturation in, 50 
pumping in, 54, 55* 
regulation of the temperature in, 

52. 53 
remedy for packing in, 54 
Leather, alligator, 466-469 
and birch oil, 486, 487 
assorting of, for dyeing, 555 
belting, to remove grease from, 

408, 409 
black, to put a gloss on, 505, 506 
blacking, coloring and dressing 
machine, Batchelder's, 257- 
262 
bleaching of, 532-538 
buffed, 432, 433 

chrome tanned, method of color- 
ing, 617, 618 



668 



INDEX. 



Leather, Danish, 412, 413 

dressing, bating of, in the United 
States, 160 

dyeing of, 553-616 

enameled, patent, furniture or 
upholstering, regalia, 436-460 

finishing machine, Bowers rocker- 
motion, 263-265 

frame for stretching, 441-443 

German harness, 395-397 

glazing and glossing of, 612-615 

grain and split, 418-435 

hard, 112 

harness and belting, 390-411 

heavy, bleaching of, 537, 538 

upper, practice of handling, 
184 
splitting the sides in the 
manufacture of, 188 

horse, 461-465 

imparting a light color to, 538- 
540 

list of patents relating to the 
manufacture of, 639-654 

making of, without tanning 
elements, 179-181 

manufactories, Russia, locations 
of, 476 

methods of dyeing used in Ger- 
many, 574-616 

over-bated, 153 

planimeter for showing the area 
of, 281 _ 

preparation of, for dyeing, 584 

raw products for, 21 

Russia, manufacture of, 475-484 

russet, 414-417 

sample of, tanned with quebracho 
extract, 39 

scoured, preparation of hides for, 
386 

sorting of, for dyeing, 585, 586 

splitting of, 186-207 

hints for, 193, 194 
practice of, 188, 189 

spongy, 112 

standard of measurement of, 278 

suppleness an indispensable re- 
quisite for, 87, 88 

tallowed, currying of, 406, 407 

underbated, 153 

vache, preparation of, 397-399 

varieties of, tanned by the Den- 
nis process, 300 

washing of, rules for, 592 

weighted with sugar, testing of, 
489 

weighting of, 489, 490 



Leather, water-proofing, 245-247 
white, 511 

bluing of, 536, 537 
Leathers, chrome, dyeing of, 323- 
325 
-tanned, preparation 
of, for dyeing, 322 
kid or morocco, 326-378 
lace, 542-552 
light, puriug of, 158, 159 
machines for measuring, 277-281 
sheep, 507-525 
] Lemon yellow on leather, 557 
on sheep-skins, 523 
Lifting pumps, 13, 14 
Light brown on leather, 556 

ochre yellow on glace leather, 604 
olive green on leather, 557 
Lime, 86-97 

action of, 94 

air-slaking of, 87 

effect of, when left in leather, 159 

for vache leather, 399 

tanners' use, slaking of, 87 
inconveniences in the use of, 87 
in water, recognition of, 5 
necessity of the removal of, from 

hides and skins, 155 
pit, old, well-plunged, analysis of 
a sample of liquor from an, 116, 
117 
pits, management of, 89, 90 
preparation of, 86 
purpose of the use of, 93, 94 
putrid, effect of, 112, 113 
Russian method of freeing hides 

from, 478 
stones, 87 
substitution of acid liquors for, 

90 
vat, new, preparation of a, 91 r 

94,95 
vats, construction of, 91 

in a kid or morocco factory, 
331, 332 
Limes, arsenic, 335 
cleaning of, 420 
effect of sodium sulphide in the, 

104 
for Dongola calf, 375 
old, use of, 92 

treatment of calf-skins in the, 90 
Liming, economies and improve- 
ments in, 93 • 
goat skins, 377 
object of, 420 

process, inconveniences of, 88 
time employed for, 92, 93 



INDEX. 



669 



Liming, too long continued, effect of, 

26 
Lining, binders and skivers, 512, 513 
Linseed, constituents of, 454, 455 

driving off the mucilage from, 

459 
oil, 454-460 

boiled, test for, 459 

by extraction, 455 

chemical changes induced in, 

by exposure to the air, 458 
cold drawn, 455 
commercial forms of, 458 
detection of adulterations of, 

457 
ordinary, 455 
properties of, 455, 456 
raw, boiling of, 444, 445 
reasons for boiling, 459 
reactions of, with acids, 456, 

457 
selection of, 458 
uses of, 457, 458 
Liquor, sour, plumping by means of, 

173-175 
Liquors, sour, distillation of, 174, 175 
Live-oak wood, 47 
Loescher's method for manufacturing 

lace leather, 547 
Logwood, 33 

and potassium chromate, dyeing 
with, 610, 611 
tannin, dyeing with, 611 
creme of, 559, 560 
Lombardy poplar bark, 45 
Louisiana, alligator hunting in, 466 

MCKAY counters, 389 
McMillan, Walter G., on Indian 
harness leather, 400-405 
MacBride, David, introduction of 
plumping by means of sul- 
phuric acid by, 175 
use of hydrochloric acid as a bate 
by, 164 
Machine belt leather greased with 

tallow. 405, 406 
Machines for measuring leathers, 
277-281 
rolling, pebbling, glass- 
ing or polishing, finish- 
ing, etc., 263-272 
Magnesia in water, recognition of, 5 
Magnesium hypochlorite, bleaching 

with, 536 
Mail bags, United States, leather for, 

414 
Maize yellow on glace" leather, 604 



Malabar kino, 29 
Malpighui's net, 21 
Manganese alum, 283, 284 
Manasse's method for tawing sheep- 
skins, 519 
Manure bate, danger of, 154 
Maroon or claret on sheep-skins, 524 
Martin's improved finishing machine, 
267, 268 
staking machine, 275, 276 
tan-press, 71-73 
Mason, Wm. M., building for sweat- 
ing hides or skins invented by, 121- 
124 
Massachusetts, varieties of leather 

produced in, 419 
Measurement of leather, standard of, 

278 
Measures and weights, 500 
Measuring leathers, machines for, 
277-281 
machine, Sawyer's, 277-279 
Union, 279-281 
Memel, horse hides for, 465 
Menhaden, 228 
fishery, 228 
oil, detection of, in cod oil, 225 

tanning principle of, 234 
Straits or Bank oil, 228, 229 
Merritt, F. S., patent of, for produc- 
ing japanned leather in imitation 
of alligator skin, 453, 454 
Mesquite oak wood, 47 
Michigan, varieties of leather pro- 
duced in, 419 
Mill bands, currying strap butts for, 
407,408 _ 
for goat skins, 377 
softening, used in Philadelphia, 
Penna., 84, 85 
Mimosa, 47 
Mimotaunic acid, 571 
Mineral acids, plumping with, 178 
colors, dyeing with, 608, 609 
or chrome tannage, 289-304 
tanning, antiquity of, 282 

substances, chrome or 
mineral tannage, 
characteristics of 
c h r o m e-t a n n e d 
leather, currying, 
dyeing, 282-325 
principal, 282 
Mixed color, 608, 609 
Moellon oil, French, 227 
Monk's scouring machine, 209-212 
Mordant, depth of a color dependent 
on the quantity of, 575 



670 



INDEX. 



Mordant, fixation of coloring matter 
by a, 574, 575 
t for Russia leather, 482 
of tin salt, preparation of a, 575.576 
Mordants, 561 , 562 
definition of. 554 
for calf leather, 570 

fur skins, 496 
groups of, 554 
Morocco, coloring of, 374, 375 

factory, drying loft in a, 364, 365, 
369, 370 
finishing room in a, 366, 367 
rolling and glazing room of 
a, 371, 372 
leather, color mixtures for, 581 

water-proofing of, 247 
manufacture, re volution in the, 326 
or kid factory, lime vats in a, 
331, 332 
leathers, 326-378 
sorting of, for dyeing, 585 
tanners of Philadelphia, Penna., 
softening mill used by, 84, 85 
Moss bunker, 228 
Muriatic acid, 353 

action of, upon hyposulphite 
of soda, 355 
Musk ox, clipped, imitation of seal 
skin in, dyeing of, 498 
long-haired, light brown for, 
498 
Myrobalans, 33 

NAPHTHA, use of, as a reducing 
agent, 450 
Naphthalene sulphonic acid, 156 
Neatsfoot oil, 228, 229, 230 
Newfoundland cod oil, 223 
New York, varieties of leather pro- 
duced in, 419 
Zealand, tanned sheep-skins 
from, 571 
Nigrosin color, blue black, 612 

deep black, 612 
"Norris" black, 374 
Norris, Wm. M., on chrome-tanned 
leather, 328- 
330 
coloring, 374, 

375 
Schultz's pat- 
ents, 346, 347 
patent of, for coloring 
chrome- 
tanned 
leather, 
617. 618 



Norris, Wm. M., patent of, for tawing 

hides or 
skins, 
618-622 

Nourishing, 595, 596 

Nutria, imitation, in clipped rabbit, 
dyeing of, 498 

OAK bark, 34, 35 
with quebracho, method for 
employing, 42, 43 
tanned sole leather, schedule of 
the time and 
strength o f 
liquor em- 
ployed in each 
layer for, 383, 
384 
unscoured and 
scoured leath- 
er, cut soles, 
379-389 
Oil, best, for leather, 223 

brown seal ; detection of, in cod 

oil, 225 
distinct classes of bodies em- 
braced in the name of, 222 
dressed leather, French method 

for tanning, 232 
dressing skins, American process 
of, 232, 233 
European method 
of, 233 
for Dongola calf, 375 

plow grain, 429 
goat, finishing of, 373, 374 
grain, blacking of, 424 

finishing of, 430 
menhaden, detection of, in cod 

oil, 225 
of vitriol, properties of, 176, 177 
porpoise, 229 
tunny, 229 
Oils and grease, curriers', 221-228 
fixed or fatty, 222 
mineral, 222 

detection of. in cod oil, 225 
testing of, 240, 241 
volatile and essential, 222 
Old grain, 121 
Olein, 223 
Oleo-stearine, 227 
Olive brown on leather, 556 

on glace leather, 606 
Oliver, C. P., and Howell, T. P., 
frame for stretching leather in- 
vented by, 441-443 
Orange on leather, 557 



INDEX. 



671 



Orange on morocco leather, 581 
Organic acids, use of, as a bate, 164 
substances in water, recognition 
of, 5 
Ox-blood shade, correct, on c h r ome- 

tanned 
calf- 
skins, 
direc- 
tions 
for, 373, 
574 
combina- 
tion tan 

or 
straight 
gam bier 
tanned 
calf- 
skin s, 
formula 
for, 567, 
568 

PADDLE method of dyeing, 558 
wheels for handling, 170, 171 
Palermo fig soap, formula for making 
fat liquor with, 243 
stuffing or fat-liquor- 
ing with, 242, 243 
Palmetto root, 44, 45 
Palmitin, 223 
Paraffine oil, for rendering leather 

pliable, 615 
Paraffine wax, 227, 235, 236 
■Paste for upper splits and calf-skins, 
427 
wax stock, 427 
Patch er, the, 443 

Patent leather factory, drying oven in 
a, 447 
tanning vats in, 
438 
furniture or upholstering 
leather, regalia leather, 
enameled leather, 436- 
460 
preserving the gloss on, 451 
smooth finished, 447-449 
black varnish 
for, 448 
stuck together, a good way 

to open, 451 
stuffing for, 440, 441 
phosphine, sample of leather, 
dyed with, 568 
Patents, list of, relating to the manu- 
facture of leather, 639-654 



Patterson, S. J., patent of, for form- 
ing an artificial grain on the hide, 
452, 453 
Payen's apparatus for distilling birch 

oil, 48b 
Peabody, Mass., manufacture of India 

tanned goat in, 364 
Peach wood, extract of, 559 
Pebble grain, finish for, 431 

very bright, 431 
finishing of, 425 
goat, finishing of, 373 
stuffing for, 424 
Pebbling and finishing machine, 
Knox improved inclined bed, 
268-271 
glassing or polishing, finishing, 
rolling, etc., machines for, 263- 
272 
or rolling jack, straight bed, 266, 
267 
Peirson-Moor process of depilating, 

116 
Peltries, deer-skins and furs, tanning 

of, 493. 494 
Pendulum jack, Coombs, 271, 272 
Pennsylvania, varieties of leather 

produced in, 419 
Percolation, 55 
Petroleum, 222 

Pfanhauser, preparation of basic 

ferric sulphate according to, 290 

Philadelphia, Penna., softening mill 

used in, 84, 85 
Phosphine, patent, sample of leather 

dyed with, 568 
Phosphoric acid, use of, as a bate, 

164 
Phyllocitannic acid, 45 
Picric acid, priming with, 554 

green on leather, 557 
Pigeon gray on glace leather, 606 

production of modifications 
with, 575* 
manure, 158 
Pin-mill, 331 
Pine tar and birch tar, differentiation 

of, 488 
Pink on sheep-skins, 524, 525 
Planimeter, Bolton, 281 
Plow grain, 428, 429 

blacking of, 424 
oil for, 429 
stuffing for, 428 
Plumping, 173, 342 

and handling, 167-178 
by means of acetic acid, 177, 178 
sour liquor, 173-175 



672 



INDEX. 



Plumping by means of sulphuric acid, 

175-177 
Pocket book, bag, case, welt and 
strap leather, and flexible splits, to 
dress, 637, 638 
Pogy, 228 
Pohle airlift pump, efficiency of the, 17 

system of raising water, 15-20 
Polishing or glassing, finishing, roll- 
ing, pebbling, etc., machines for, 
263-272 
Pompeian red on glace leather, 605 
Porpoise oil, 229 
Potash alum, 283 

chloride of, 355 
Potassium bichromate, 285, 286, 330 
and hyposulphite of 
soda,determination 
of the proper re- 
lation between, 354 
combinations, 285 
rule for finding the 
combining weight 
of, 352, 353 
solubility of, 285 
chromate and logwood, dyeing 

with, 610, 611 
ferrocyanide of, 561 
permanganate, bleaching with, 

536 
xanthogenate, 120, 121 
Power, electric transmission of, 636, 

637 
Press leach system, 60, 61 
Protaceae barks, 46 
Pumping machinery, prominence of, 

in engineering, 12 
Pump, invention of the, 13 
Pumps, 12-20 

and water, 1-20 
atmospheric, 13, 14 
lifting, 13, 14 
Pure run, 155 
Puring, 153, 378 

definition of, 161 
Putting-out machine, 356-358 

QUEBRACHO, 36, 44 
advantages in the use of, 
41, 569 
analysis of, 39 
cost of, 44 
extract, 44 
-tanned leather, sample of, 

569 
with oak bark, method 
for employing, 42, 43 
Quercitron, 35 



RABBIT, clipped, imitation nutria 
in dyeing of, 498 
skins, black on, 616 
dyeing of, 497 
Raising, 88, 89 
process of, 92 
series, 92 
Ratanky root, 47 
Red, alizarine, on leather, 556 
oak bark, 35 
brown to dark brown on glace 

leather, 606 
dye for Russia leather, 481 
on cordovan leather, 581 
genuine Russia leather, 580 
leather, 556 
morocco leather, 581 
tawed leather, 582 
ordinary, on leather, 557 
Pompeian on glace leather, 605 
wood, extract of, 559 
Reddish brown to Venetian red on 

glace leather, 605 
Reducing, 153 
Reed and Winchester's stuffing drum, 

218-2120 
Reel, handling by means of a, 167, 168 

treating skins in a, 337, 338 
Regalia leather, 450 

enameled leather, patent 
leather, furniture or up- 
holstering leather, 436- 
460 
Register straps, leather for, 415 
Richardson, Alpha, patent of, 186 
Robertson's grinding adjustment for 
belt_ knife splitting machines, 
203-207 
Rocker handler, the, 168 

-motion leather finishing ma- 
chine, Bowers, 263-265 
Rockers, 382 

liquors supplied to the, 382, 383 
spent liquors from, 57 
Rolling and glazing room of a mo- 
rocco factory, 371, 372 
machine for sole leather, 386, 

387 
or pebbling jack, straight bed, 

266, 267 
pebbling, glassing or polishing, 
finishing, etc., machines for, 
263-272 
Rolls, glazing, 615 
Rood improved shaving machine, 

254, 255 
Rove, 31 
Rusma, 109 



INDEX. 



673 



Russet harness leather, bleaching of, 
537, 008 
leather, 414-417 
dyeing of, 417 
printing of, 41 G 
Russia calf, 470-474 

coloring of, 473, 474 
dyed samples of, 564 
coloring matter for Russia leather 

used in, 482 
leather, cause of the peculiar 
odor of, 476 
black colored, 484 
genuine, color mixtures for, 

'580, 581 
manufacture of, in the United 
States, 480- 
482 
Russian method 
of preparing 
and applying 
the mordant 
and dye, man- 
ufacture of 
birch oil, 475- 
488 
red dye for, 481 

color of, 480 
uses of, 475 
locations of leather manufactories 

in, 476 
mordant for Russia leather, used 

in, 482 
odor to calf leather, 488 
oil, 484 

preparation of birch oil in, 478, 479 
Rutea, 29 

QADTLER, Prof. S. P., experiments 

O of, 341 

Sal, 401 

Salt, basic or oxy, 313 

common, 288, 289 

Syracuse coarse, for curing hides, 
381 
Salts, most important, used in leather 

dyeing, 554, 555 
Sammying russet leather, 416 
Samples of dyed leathers, 561-569 
Sandstone filter, Foster's, 594, 595 
Sassafras root, 47 
Satin grain, stuffing for, 422 

oil, blacking of, 424 
finish for, 481 
finishing of, 424, 425 
Saw-toothed flesher, 136 
Sawyer's leather measuring machine, 

277-279 „. 

43 



Scarlet 011 leather, 556, 557 
Schmitz-Dumont, Dr. W. on deter- 
mination of tanning matters, 633- 
636 
Schroeder, J. V., and Schmidt-Du- 
mont, W., on the chemistry of 
depilatories, 116-120 
Schultz, Augustus, circular of, 347-319 
early experiments of, 

327 
essential d i s c o ve r y 

made by, 339 
Wm. M. Norris, on the 

patents of, 346, 347 
patents of, 326 
specification of first 

patent of, 343-345 
specification of second 

patent of, 345, 346 
transfers of patents of, 
327,328 
Schultz's method of tanning, 297, 298 
process, tawing skins according 

to the, 336-343 
two bath process, 297 
Scorza rosa, 46, 47 
Scoured leather, preparation of hides 

for, 386 
Scouring, 166, 208-214 

and setting-out machine, 212-214 
indications of the readiness of 

hides for, 139, 140 
hand method of, tools used in the, 

208. 209 
machine, Monk's, 209-212 
tables and other mechanical de- 
tails of hand method of, 208, 209 
Seal and hog, imitation, 427, 428 

skin, imitation of, in clipped 

musk-ox, dyeing of, 498 
oil, brown, detection of, in cod 
oil, 225 
Seasoning composition, 360 

for straight-grained goat, 369 
machine, 358-360 
Sepia brown on glace leather, 606 
Setting-out, 248, 249 

tables for, 217 
Shaving and whitening leather, 25C- 
255 
machine, 254, 255 
Sheep leather, glove, natural tan 
sample of, 565 
leathers, 507-525 
-skin, dyed sample of, 565, 566 
flesher, 512 

fleshers, dressing of, for glove 
bindings, 513, 518, 519 



674 



INDEX. 



Sheep-skin, pickle, dved sample of, 
565, 566 
tanner}^, drying loft in a, 513, 
516 
exterior view of a, 512, 

514 
finishing room in a, 513, 

517 
tanning vats in a, 513,515 
-skins, bark tanned, dyeing of, 
intense dull black, 525 
blue-reddish on, 522 

-bluish on, 522 
claret or maroon on, 524 
cochineal on, 523 
coloring for, 522-525 
composition for removing 
the hair from, 520 
for tanning, 520 
grass-green on, 523, 524 
Hestahl's process for dress- 
ing, 520, 521 
Hibbard's method for pre- 
paring and tanning, 520 
lemon yellow on, 523 
liming of, 94 

manufacture of, into lining, 
binders and skivers, 512, 
513 
pink on, 524, 525 
removal of grease from, 94, 

508, 509 
scabby, 95 
solferino on, 525 
tanning of, by the chrome 

process, 306 
tawing of, Manasse's method, 

519 
unhairing of, 508 
uses of, 507, 508 
Shoe leather, brown, 571 

proper way of splitting, 
415,416 " 
purposes, horse hides for, 462- 

464 
work, dyeing calf-skins for, 572, 
573 • 
Shoes, dyeing of leather for, 571-573 
sporting, demand for, 303, 304 
varieties of colored leather for, 
573 
Shorea Robusta, 401 
Short hair knife, 133 
Shute and Faulkner's seasoning ma- 
chine, 358-360 
Sicilian sumach, 31 
Side leather, frames for japanning, 
444 



Sides, best bate for, 158 

for grain and split leathers, hand- 
ling of, 1 72 
handling the, bv means of a reel, 

167, 168 
modes of connecting, 168 
splitting of, in the manufacture 
of heavy upper leather, 188 
Sienna brown on glace leather, 605 
Silicic acid in water, recognition of, 5 
Silk dyeing, application of the alaza- 

rines in, 324 
Skin, animal, 21-28 

behavior of the, under various 

conditions, 24 
chemical and morphological con- 
stitution of, 24, 25 
cleansing the, with borax, 52 
explanation of the effect of 
sodium sulphide on the grain 
of the, 1-4, 105 
fibre, most important property 

of, 28 
fibroin, 28 
"killing" the, 496 
practice of reducing the, 161 
tissue, absorption of alum by the, 

284 
transverse section of, 22, 23 
Skins and hides, preparation of, for 
soaking, 79-81 
working out and un- 
hairing all kinds of, 
without limes, bate, 
drench or beaming, 
116 
consequence of the use of too 
concentrated solutions of tan- 
nin for, 390 
depilous, 86 

final step in the process of tan- 
ning, 181 
oil dressing, American process 

of, 232, 233 
or hides, art of tawing, 618-622 
building for sweating, 
121-124 
separation of, in classes for dye- 
ing, 585, 586 
soaking of, 79 
softening of, 84 
sumach tanned, 364-366 
unhairing of, by the hand 

method, 130-135 
washing the, for dyeing, 586-588 
with the hair on, bleaching of, 
_ 540, 541 
Skirting, curriers', 395 



Index. 



675 



Skivers, binders and lining, 512, 513 
Slate gray on glace leather, GUT 
Slater, the, 336, 378 
Slicker, 208 
coat, 446 
softening, 36S 
whitening, 250 
Slocomb & Co., hand-method stak- 
ing machine, built by, 273, 274 
Smiley, R. W., and Gopelrivitch, re- 
port of, on alligator hunting, 406 
Smith, Oliver C, patents of, 251 
Smooth finished patent leather, 447- 
449 
leather, black 
varnish for, 
448 
Smutting, 433 

off or bleeding of colors, 563, 504 
Suouba bark, 40, 47 
Soak, chemical, 82 
Soaking and softening, 78-85 

final, before placing the hides in 

the ooze, 166 
hides after fleshing by the hand 
method, 138, 139 
in a steeping cistern after 
fleshing, 139 
Soaks, 330 

change of water in the, 379 
use of pure water in the, 83 
Soap, Palermo fig, stuffing or fat- 
liquoring with, 242, 1^43 
solution for determining the 
hardness of water, 6 
Soaps 555 

Sod oil, American, 233 
artificial, 234 
conversion of fish oil to, by 

oxidation, 234 
early use of, 231 
English, 226, 227 
European, 233 
French, 233 

pure, tanning principle of, 234 
sulphuric acid in, 231 
Soda, hyposulphite of, 287 

use of, for softening water, 593, 
594 
Sodium bichromate, 286 

peroxide, bleaching with, 535 
sulphide, advantages of, 99 
depilating with, 97—113 
effect of, in the limes, 104 
explanation of the effect of, 
on the grain of the skin, 
104, 105 
grades of, 98, 99 



Sodium sulphide, improved, 100 

in connection with lime, 

method of using, 98 
method of using, 102, 103 
plumping properties of, 106 
properties of, 100 
results obtained by, 111 
summary of the good quali- 
ties of, 105 
undesirable qualities of, 105- 
107 
Softening, 84, , y 5 

and soaking, 78-85 

machine, Tidd's, 549-552 

mill, used in Philadelphia, Penna., 

84, 85 
slicker, 368 
Sole leather, American, export trade 
in, to Germany, 40 
analysis of a sample of, 

489, 490 
bate for, 160, 161 
bating the hides for, 381 
chrome tannage for, 302 
drying of, 385 
layers and periods for, 182 
liming of, 380, 381 
method for employing 
quebracho with oak bark 
for, 42, 43 
oak tanned, laying away the 
packs of, 182 
schedule of the time 
and strength of 
liquor emplo3'ed 
in each layer for, 
383, 384 
un scoured and 
scoured leather, 
cut soles, 379-389 
process for using pure 
quebracho wood for, in 
Buenos Ayres, 41 , 42 
rolling machine for, 386, 

387 
scudding the grain of, 381 
situation in the United 

States, 43 
softening dry hides for, 82 
Soles, cut, 387-380 
Solferino on sheep-skins, 525 
Solutions, theor} 7 of, 576, 577 
Sorting leather for dyeing, 585, 586 
Sour liquor, plumping by means of, 
173-175 
liquors, distillation of, 174, 175 
South American hides, 379 
Spanish sumach, 32 



676 



INDEX. 



Split and grain leather, 418-435 
frames, 444 

leather, handling of sides for, 172 
preparing the cut surface of, 
for manufacturing japan- 
ned or enameled leather, 
452, 453 
Splitting card leather, 416 
leather, 186-207 

hints for, 193, 194 
leathers, instructions in regard 

to, 198-200 
machines, 186-198 
shoe leather, proper way of, 415, 

416 
strap leather, 416 
Splits, blacking for, 427 

crimping, finishing of, 425, 426 
flesh, 429-432 
flexible, 433-435 

to dress, 637, 638 
kinds of leather derived from, 444 
trimming of, 421 
upper, paste for, 427 
Sporting shoes, demand for, 303, 304 
Spring fleshers, 136 

water, admixtures of, 2 
Stag's leather, bleaching of, 537, 538 
Stain for grain and split leather, 424 
Staking machine, 273-276 
Stakpole staking machine, 274, 275 
Starcke, Dr. H. E., analysis of spent 

bark by, 65 
Steam jacket kettles, 242 
Stearin, 223 

Steel gray on glace leather, 607 
Stevens, John W., on the sulphide of 

sodium process, 100-102 
Stone, the, 208 
Stoning, 185,217,218 
jack, 185, 415 

-out, scouring and setting-out 
machine, 248, 249 
Straight bed rolling or pebbling jack, 
266, 267 
-grained goat, finishing of, 368- 
373 
Straits, bank or menhaden oil, 228- 
229 
oil, tanning principle of, 234 
Strap butts for mill bands and engine 
belts, currying of, 407, 408 
leather, 414 

drum tannage for, 399, 400 
splitting of, 416 
pocket book, bag, case and welt 
leather and flexible splits, to 
dress, 637, 638 



Straps for street cars, leather for, 515 
Stretching hides, mechanical devices 
for, 543, 544 
machine, Coupe's, 547-549 
Striking out, object of, 364 
Strontium chromate, 286 
Stuffing, best material to use in, 216 
drum, 216-218 
Freeman's, 221 

Reed and Winchester's, 218- 
220 
for dongola, 424 

enameled or patent leather, 

440, 441 
flesh splits, 429 
glove grain, 422, 424 
imitation goat grain, 424 
kangaroo, 424 
pebble grain, 424 
plow grain, 428 
satin grain, 422 
upper leather, 227 
hand method, objections to, 215, 

216 
leather; oils and fats; testing oils; 
water-proof stuffing ; water- 
proofing leather, 215-247 
water-proof, 243 
with glycerine, 239, 240 
with Palermo fig soap, 242, 243 
Sugar, testing leather weighted with, 

489 
Sulphate of alumina, 561 

copper, 561 
Sulphates in water, recognition of, 5 
Sulphuric acid in water, recognition 
of, 5 
for bate. 164 

toning down, 539 
free, detection of, in 
aluminium sulphate, 
283 
plumping by means of, 

175-177 
properties of, 176, 177 
Sulphurous acid, apparatus for the 
production of, 534, 

535 
bleaching with, 532- 

534 
control of, 355 
Sumac, 31, 32 

tanned skins, 364-366 
Sweat box, construction of the, 127 
Sweating, depilating by, 120, 121 
fresh hides, 128, 129 
hides, care to be observed in, 
124-127 



INDEX. 



677 



Sweating process, warm, 127, 128 
Swedish sumach, 32 
"Sweet meats," 445 
Symbols, chemical, 351, 352 
Syracuse coarse salt for curing hides, 
381 

'FALLOW, 227 

machine belt leather, greased 
with, 405, 406 
Tan leather, water- proofing of, 247 
press, 71-73 

vat used in the two-bath method 
of chrome tannage, 343 
Tannage, drum, 399, 400 

chrome or mineral, 289-304 

some patents for, 306-308 
for grain and split leathers, 419 
systems, electric and other rapid, 
526-531 
Tanners' preparation for obtaining 

uniform colored leather, 562, 563 
Tanner's pump. 12 
Tanneries, location of, 1 

modern, fitting up of, 530 
Tannery, sheep-skin, drving loft in a, 
513,516 
exterior view of a, 

512,514 
finishing room in a, 

513,517 
tanning vats in a, 
513, 515 
Tannin, action of, 179 

and logwood, dyeing with, 611 

iron salts, dyeing with, 610 
combination of glycerine with ,239 
Tanning and dyeing furs and hair 
skins, 491-500 
calf-skins in the hair, 491 , 492 
calf or goat-skins by the chrome 

process, 304-306 
Dennis method of, 298-300 
extract, decolorizing process in 

the preparation of, 77 
extracts, 74-77 

examination of, 77 
leather, Dennis process of, 313- 

319 
liquor, Dennis, 308-313 
material for Indian harness 

leather, 401 , 402 
materials, vegetable, 29-47 
matters, determination of, 633- 

636 
mineral, antiquity of, 282 
process for Indian harness 
leather, 402, 403 



Tanning process, nature of the, 591 

quick, for harness leather, 
392 
processes, quick, revolution in, 

527,528 
quick, use of borax in, 52 

with chromates, Heinzer- 
ling's patent for, 293-296 
Schultz's method of, 297, 298 
sheep-skins by the chrome pro- 
cess, 306 
substances, mineral, principal, 

282 
vats in patent leather factory, 438 
sheep-skin tannery, 513, 
515 
Zahn's patent for, 349-351 
Tanolin, 298, 299 

directions for using on calf or 
goat-skins, 304-306 _ 
Tawed leather, color mixtures for, 
581, 582 
dyeing of, 598 
not dyed, glazing of, 613 
sorting of, for dyeing, 585 
washing of, for dyeing, 586, 
587 
Tawing, 336-343 

hides of skins, art of, 618-622 
lamb and kid skins for glove 

leather, dyeing, 501-504 
sheep-skins, Manasse's method 
for, 519 
Tempering, 215 
Terra japonica, 29, 30 
Testing oils, 240, 241 
Tests of new Indian harness leather, 

404, 405 
Texas hides, 379 
Tezera sumach, 32 
Thibet, dark brown for, 4^7 
Tidd's softening machine, 549-552 
Tin salt, preparation of a mordant of, 

575, 576 
Toiling fluids, 578-580 

action of, 578, 579 
and dyes, 603, 604 
preparation of, 579, 580 
Top leather, black enameled, 444- 

447 
Tormentil root, 47 
Towein's graining machine, 483 
Tramping drums, improvement in, 

220, 221 
True skin, 21, 22 
Tub wheel, the, 543 
Tumbling barrel, soaking hides in, 78 
Tunny oil, 229 



678 



INDEX. 



Turning steel, three square, 137 
Tyrol sumach, 32 

UNDER-SKIN, constitution of, 22 
Unhairing and fleshing by hand 
and ma- 
chinery, 
130-152 
by machinery, 

140-152 
m achines, 
practical 
success of, 
151 
knife, 130 
machines, 146-148 
methods for accomplish- 
ing, 86 
or depilation, 86-129 
Union leather, cloudy and dirty, 381 
measuring machine, 279- 
281 
splitting machine, 188 

hints with the use 
of the, 193, 194 
tannage, 34 

whitening and buffing machine, 
251-254 
United States, bating dressing leather 
in the, 160 
leather situation in the, 43 
list of patents relating to 
the manufacture o f 
leather issued by the, 
639-654 
location of tanneries and 
currying shops in the, 1 
mail bags, leather for, 414 
manufacture of Russia 

leather in the, 480-482 
tanning extracts in com- 
mon use in the, 74 
Unscoured and scoured leather, oak- 
tanned sole leather, cut soles, 379- 
389 
Upholstering or furniture leather, fin- 
ishing of, 449 
leather, regalia 
enameled 
leather,patent 
leather, 436- 
460 
Upper leather, bate for hides for, 140 
chrome, 301 

heavy, practice of hand- 
ling, 184 
lime for green hides and 
kips for, 399 



Upper leather, requisite qualities of, 
418 
stuffing for, 227 
tannery, cellar of an, 186 
drying yard of an, 422, 
423 
whitening of, 250 
splits, paste for, 427 
Uppers, burnt, 302 
Ursol colors, 495 

advantage in dyeing with, 

499 
blue-black tinge with, 498, 
499 

\fACHE leather, preparation of, 
397-399 
Valonia, 32, 33 

Varnish, black, preparation of, 448 
brushes, 451 
enameled, 446 

finishing for smooth finished 
patent leather, 449 
Vaseline, use of, for rendering leather 

pliable, 615 
Vats, lay-away, 181, 383 
Vaughn Machine Co., bark-cutter 
made by the, 
66,67 
breaking, flesh- 
ing, unhairing 
and slating 
machine made 
by the, 331, 
333, 334 
Coombs pendu- 
lum jack made 
by the, 271,272 
improved flesh- 
ing, unhairing 
and workiug- 
out machine 
of the, 140-145 
leach pumps 
made by the, 
52 
putting-out ma- 
chine built by 
the, 356-358 
Rood improved 
shaving ma- 
chine, man- 
ufactured by 
the, 254, 255 
scouring and 
s e 1 1 i n g-o u t 
machine, built 
by the, 21 2-21 4 



INDEX. 



679 



Vaughn Machine Co., staking ma- 
chine built by 
the, 274, 275 
s t o n i n g-o u t, 
scouring and 
setting-out 
machine, built 
by the, 248,249 
wet stretching 
machine for 
belt leather, 
made by the, 
409-411 

Vegetable tanning materials, 29-47 

Velocitan process of quick tannage, 
527 

Vickers' degras, 231 

Villon, experiments by, 120, 121 

Violet on tawed leather, 582 

Vitriol, oil of, properties of, 176, 177 

WALNUT bark, 45 

W Warm sweat method, 121, 127, 

128 
Warrington, use of carbonate of am- 
monia as a bate by, 164 
Wash mill, 377 

Washing and bating, vats and wheels 
for, 165 
leather, rules for, 592 
machine, the, 588-590 
Water, analysis of, from the Ganges 
canal, 401 
and pumps, 1-20 
borax for softening, 83, 594 
degrees of hardness of, !) 
for dyeing, quality of the, 593- 

595 
gases held in solution in, 2 
hard, 2, 593 

importance of the chemical con- 
stitution of, 598 
important position of, in tan- 
ning, 1 
methods for determining the 

constituents of, 4-9 
most important admixtures of, 

1-3 
organic products of decomposi- 
tion in, 2, 3, 
per cent, of, in degras, 632, 633 
permanent hardness of, determi- 
nation of, 9 
•pit, 78 

arranging hides in the, 79 
Pohle system of raising, 15-20 
points to be considered in de- 
termining the qualities of, 3 



Water-proof colors, 560, 501 
stuffing, 244 
-proofing leather. 245-247 

compound for, 246 
qualitative examinations of, 4-9 
sandstone filter for, 5!)4, 595 
soda for softening, 593, 594 
soft, 2 

softening of, 9-12 
solvent properties of, 11, 12 
stripes, production of, 895 
temperature of the, for prepar- 
ing the hides, 4 
total hardness of, determination 

of, 6-8 
variation in the boiling point of, 
76 
Waters, natural, influence of, upon 

coriin, 26 
Wax finish on chrome-tanned horse 
hide butts, 464 
paraffine, 235, 236 
stock, paste for, 427 
Waxed calf, quality of the water in 
the manufacture of, 18 
temperature of the water in 
the manufacture of, 15 
Weighting of leather, 489, 490 
Weights and measures, 500 
Weld, 34 

Welt, strap, pocket book, bag and 
case leather, and flexible splits, to 
dress, 637, 638 
Well water, admixtures of, 2 
Wet stretching machine for belt 

leather, 409-411 
Wheels, soaking hides in, 78 
Whip and lace leather, quick tanning 

process for, 546, 547 
Whipstocks, leather for, 414 
White leather, 511 

bluing of, 536, 537 
oak bark, 35 
Whitening and buffing machine, 
Union, 251-254 
shaving leather, 
250-255 
slicker, 250 
Whitney's "Jumbo " uuhairing ma- 
chine, 146, 147 
patent combined unhairing, 
fleshing and working-out ma- 
chine, 147-149 
patent re-fleshing machine, 149, 
150 
Wild goat, dark brown for, 497 
grey-brown for, 497, 498 
Willow bark, 46 



68o 



INDEX. 



Willow tannage for Danish leather, 
412 

Wisconsin, varieties of leather pro- 
duced in, 419 

Wood brown to mahogany color on 
glace leather, 605 
dyes, advantage of, 558 

Wool waste, American degras from, 
631,632 

Worker, the, 137 

Worms, B., tanning process of, 526 

YELLOW, barberry, on leather, 557 
chrome, on leather, 557 
lemon, on leather, 557 
light ochre, on glace leather, 604 



Yellow maize, on glace leather, 604 
on cordovan leather, 5S1 

morocco leather, 581 

tawed leather, 582 
Yolk of egg, preservation of, 597 
Young fustic, 559 

ZAHN, W., first production of com- 
mercial leather tanned 
by Schultz's process by, 
298 
patent, specification of the, 
349-351 
Zane, Oliver A., bark conveyor in- 
vented by, 68-71 



CA.TJLLOO-TTE 

OF 

practical and {Scientific Boo^ 

PUBLISHED BY 

Henry Carey Baird & Co, 



INDUSTRIAL PUBLISHERS, BOOKSELLERS AND IMPORTERS. 

810 Walnut Street, Philadelphia. 



-8®= Any of the Books comprised in this Catalogue will he sent hy mail, free of 
postage, to any address in the world, at the publication prices, 

4®=- A Descriptive Catalogue, 90 pages, 8vo., will he sent free and free of postage, 
to any one in any part of the world, who will furnish his address. 

*3r- Where not otherwise stated, all of the Books in this Catalogue are bound 
in muslin. 



AMATEUR MECHANICS' WORKSHOP: 

A treatise containing plain and concise directions for the manipula- 
tion of Wood and Metals, including Casting, Forging, Brazing, 
Soldering and Carpentry. By the author of the " Lathe and Its 
Uses." Seventh edition. Illustrated. 8vo. . . . $2.50 

ANDRES. — A Practical Treatise on the Fabrication of Volatile 
and Fat Varnishes, Lacquers, Siccatives and Sealing 
Waxes. 
From the German of Erwin Andres, Manufacturer of Varnishes 
and Lacquers. With additions on the Manufacture and Application 
of Varnishes, Stains for Wood, Horn, Ivory, Bone and Leather. 
From the German of Dr. Emil Winckler and Louis E. Andes. 
The whole translated and edited by William T. Brannt. With 11 
illustrations. i2mo. ....... $2.50 

ARLOT.-A Complete Guide for Coach Painters : 

Translated from the French of M. Arlot, Coach Painter, for 
eleven years Foreman of Painting to M. Eherler, Coach Maker, 
Paris. By A. A. Fesquet, Chemist and Engineer. To which is 
added an Appendix, containing Information respecting the Materials 
and the Practice of Coach and Car Painting and Varnishing in the 
United States and Great Britain- T2mo. . . . $1.25 

(0 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 



ARMENGAUD, AMOROUX, AND JOHNSON.— The Practi- 
cal Draughtsman's Book of Industrial Design, and Ma- 
chinist's and Engineer's Drawing Companion : 

Forming a Complete Course of Mechanical Engineering and Archi- 
tectural Drawing. From the French of M. Armengaud the elder, 
Prof, of Design in the Conservatoire of Arts and Industry, Paris, and 
MM. Armengaud the younger, and Amcroux, Civil Engineers. Re- 
written and arranged with additional matter and plates, selections from 
and examples of the most useful and generally employed mechanism 
of the day. By William Johnson, Assoc. Inst. C. E. Illustrated 
by fifty folio steel plates, and fifty wood-cuts. A new edition, 410,, 

half morocco . $7.50 

ARMSTRONG.— The Construction and Management of Steam 
Boilers : 
By R. Armstrong, C. E. With an Appendix by Robert Mallet, 
C. E., F. R. S. Seventh Edition. Illustrated. 1 vol. i2mo. 75 

ARROWSMITH.— Paper-Hanger's Companion : 

A Treatise in which the Practical Operations of the Trade are 
Systematically laid down : with Copious Directions Preparatory to 
Papering; Preventives against the Effect of Damp on Walls; the 
various Cements and Pastes Adapted to the Several Purposes oi 
the Trade ; Observations and Directions for the Panelling and 
Ornamenting of Rooms, etc. By James Arrowsmlth. 3 2rno., 
cloth $1.00 

ASHTON. — The Theory and Practice of the Art of Designing 
Fancy Cotton and Woollen Cloths from Sample : 

Giving full instructions for reducing drafts, as well as the methods of 
spooling and making out harness for cross drafts and finding any re- 
quired reed; with calculations and tables of yarn. By Frederic T. 
Ashton, Designer, West Pittsfield, Mass. With fifty-two illustrations. 
One vol. folio - • $6.00 

aSKINSON. — Perfumes and their Preparation : 
A Comprehensive Treatise on Perfumery, containing Complete 
Directions for Making Handkerchief Perfumes, Smelling-Salts, 
Sachets, Fumigating Pastils ; Preparations for the Care of the Skin, 
the Mouth, the Hair; Cosmetics, Hair Dyes, and other Toilet 
Articles. By G.W. Askinson. Translated from the German by IsiDOR 
Furst. Revised by Charles Rice. 32 Illustrations. 8vo. $3.00 

8AIRD.— Miscellaneous Papers on Economic Questions. 
By Henry Carey Baird. {In preparation.) 

BAIRD.— The American Cotton Spinner, and Manager's and 
Carder's Guide: 
A Practical Treatise on Cotton Spinning ; giving the Dimensions and 
Speed of Machinery, Draught and Twist Calculations, etc. ; with 
notices of recent Improvements : together with Rules and Examples 
ibr making changes in the sizes and numbers of Roving and Yarn. 
Compiled from the papers of the late Robert H. Baird. i2mo. 

#1.50 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 



9AIRD. — Standard Wages Computing Tables : 

An Improvement in all former Methods of Computation, so arranged 
that wages for days, hours, or fractions of hours, at a specified rate 
per day or hour, may be ascertained at a glance. By T. Spangler 
Baird. Oblong folio ....... $5.00 

3AKER. — Long-Span Railway Bridges: 
Comprising Investigations of the Comparative Theoretical and 
Practical Advantages of the various Adopted or Proposed Type 
Systems of Construction; with numerous Formulae and Tables. By 
B. Baker. i2mo. #1.50 

BAKER. — The Mathematical Theory of the Steam-Engine ; 
With Rules at length, and Examples worked out for the use of 
Practical Men. By T. Baker, C. E., with numerous Diagrams. 
Sixth Edition, Revised by Prof. J. R. Young. i2mo. . 75 

BARLOW. — The History and Principles of Weaving, by 
Hand and by Power : 
Reprinted, with Considerable Additions, from " Engineering," with 
a chapter on Lace-making Machinery, reprinted from the Journal of 
the "Society of Arts." By Alfred Barlow. With several hundred 
illustrations. 8vo., 443 pages $10.00 

BARR. — A Practical Treatise on the Combustion of Coal: 
Including descriptions of various mechanical devices for the Eco- 
nomic Generation of Heat by the Combustion of Fuel, whether solid, 
liquid or gaseous. Svo. ....... $2.50 

BARR. — A Practical Treatise on High Pressure Steam Boilers: 
Including Results of Recent Experimental Tests of Boiler Materials, 
together with a Description of Approved Safety Apparatus, Steam 
Pumps, Injectors and Economizers in actual use. By Wm. M. Barr. 
204 Illustrations. Svo. . ..... $3.00 

BAUERMAN.— A Treatise on the Metallurgy of Iron: 

Containing Outlines of the History of Iron Manufacture, Methods of 
Assay, and Analysis of Iron Ores, Processes of Manufacture of Iron 
and Steel, etc., etc. By H. Bauerman, F. G. S., Associate of the 
Royal School of Mines. Fifth Edition, Revised and Enlarged. 
Illustrated with numerous Wood Engravings from Drawings by J. B, 
Jordan. i2mo $2.oc 

BAYLES. — House Drainage and Water Service : 

In Cities, Villages and Rural Neighborhoods. With Incidental Con. 
sideration of Certain Causes Affecting the Healthfulness of Dwell- 
ings. By James C. Bayles, Editor of " The Iron Age " and " The 
Metal Worker." With numerous illustrations. 8vo. cloth, 

BEANS. — A Treatise on Railway Curves and Location of 
Railroads : 
By E. W. Beans, C. E. Illustrated. i2mo. Tucks . $1.50 

BECKETT.— A Rudimentary Treatise on Clocks, and Watches 

and Bells : 

By Sir Edmund Beckett, Bart., LL. D., Q. C. F. R. A. S. With 

numerous illustrations. Seventh Edition, Revised and Enlarged. 

l2mo $2-2$ 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 



BELL. — Carpentry Made Easy: 

Or, The Science and Art of Framing on a New and Improved 
System. With Specific Instructions for Building Balloon Frames, Barn 
Frames, Mill Frames, Warehouses, Church Spires, etc. Comprising 
also a System of Bridge Building, with Bills, Estimates of Cost, and 
valuable Tables. Illustrated by forty-four plates, comprising nearly 
200 figures. By William E. Bell, Architect and Practical Builder. 
8vo #5-°° 

BEMROSE. — Fret-Cutting and Perforated Carving: 

With fifty-three practical illustrations. By W. Bemrose, Jr. i vol. 
quarto $2.50 

BEMROSE. — Manual of Buhl-work and Marquetry: 

With Practical Instructions for Learners, and ninety colored designs. 
By W. Bemrose, Jr. i vol. quarto .... #3.00 

BEMROSE. — Manual of Wood Carving: 

With Practical Illustrations for Learners of the Art, and Original and 
Selected Designs. By William Bemrose, Jr. With an Intro- 
duction by Llewellyn Jewitt, F. S. A., etc. With 128 illustra- 
tions, 4to. ......... $2.50 

BILLINGS.— Tobacco : 

Its History, Variety, Culture, Manufacture, Commerce, and Various 
Modes of Use. By E. R. Billings. Illustrated by nearly 200 
engravings. 8vo. ........ $3- of 

BIRD. — The American Practical Dyers' Companion: 

Comprising a Description of the Principal Dye-Stuffs and Chemicals 
used in Dyeing, their Natures and Uses ; Mordants, and How Made ; 
with the best American, English, French and German processes for 
Bleaching and Dyeing Silk, Wool, Cotton, Linen, Flannel, Felt. 
Dress Goods, Mixed and Hosiery Yarns, Feathers, Grass, Felt, Fur, 
Wool, and Straw Hats, Jute Yarn, Vegetable Ivory, Mats, Skins, 
Furs, Leather, etc., etc. By Wood, Aniline, and other Processes, 
together with Remarks on Finishing Agents, and Instructions in the 
Finishing of Fabrics, Substitutes for Indigo, Water-Proofing of 
Materials, Tests and Purification of Water, Manufacture of Aniline 
and other New Dye Wares, Harmonizing Colors, etc., etc. ; embrac- 
ing in all over 800 Receipts for Colors and Shades, accompanied by 
170 Dyed Samples of Raw Materials and Fabrics. By F. J. Bird, 
Practical Dyer, Author of " The Dyers' Hand-Book." 8vo. $10.00 

BLINN. — A Practical Workshop Companion for Tin, Sheet- 
Iron, and Copper-plate Workers : 
Containing Rules for describing various kinds of Patterns used by 
Tin, Sheet-Iron and Copper-plate Workers; Practical Geometry; 
Mensuration of Surfaces and Solids ; Tables of the Weights of 
Metals, Lead-pipe, etc. ; Tables of Areas and Circumference* 
of Circles ; Japan, Varnishes, Lackers, Cements, Compositions, etc., 
etc. By Leroy J. Blinn, Master Mechanic. With One Hundred 
and Seventy Illustrations. l2mo. ..... $2.50 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 



BOOTH. — Marble Worker's Manual : 

Containing Practical Information respecting Marbles in general, theii 
Cutting, Working and Polishing; Veneering of Marble ; Mosaics; 
Composition and Use of Artificial Marble, Stuccos, Cements, Receipts, 
Secrets, etc., etc. Translated from the French by M. L. Booth. 
"With an Appendix concerning American Marbles. l2mo., cloth $1.50 
BOOTH and MORFIT. — The Encyclopaedia of Chemistry, 
Practical and Theoretical : 
Embracing its application to the Arts, Metallurgy, Mineralogy, 
Geology, Medicine and Pharmacy. By James C. Booth, Melter 
and Refiner in the United States Mint, Professor of Applied Chem- 
istry in the Franklin Institute, etc., assisted by CAMPBELL MORFIT, 
author of " Chemical Manipulations," etc. Seventh Edition. Com- 
plete in one volume, royal 8vo., 978 pages, with numerous wood-cuts 
and other illustrations ....... $3-5° 

BRAM WELL.— The Wool Carder's Vade-Mecum, 

A Complete Manual of the Art of Carding Textile Fabrics. By W. 
C. Bramwell. Third Edition, revised and enlarged. Illustrated. 
Pp. 400. i2mo. ........ $2.50 

BRANNT. — A Practical Treatise 0*1 Animal and Vegetable 
Fats and Oils : 
Comprising both Fixed and Volatile Oils, their Physical and Chemi- 
cal Properties and Uses, the Manner of Extracting and Refining 
them, and Practical Rules for Testing them ; as well as the Manu- 
facture of Artificial Butter, Lubricants, including Mineral Lubricating 
Oils, etc., and on Ozokerite. Edited chiefly from the German of 
Drs. Karl Schaedler, G. W. Askinson, and Richard Brunner, 
with Additions and Lists of American Patents relating to the Extrac- 
tion, Rendering, Refining, Decomposing, and Bleaching of Fats and 
Oils. By William T. Brannt. Illustrated by 244 engravings. 
739 pages. 8vo. ........ $ 12.50 

BRANNT.— A Practical Treatise on the Manufacture of Soap 
and Candles : 
Based upon the most Recent Experiences in the Practice and Science ; 
comprising the Chemistry, Raw Materials, Machinery, and Utensils 
and Various Processes of Manufacture, including a great variety of 
formulas. Edited chiefly from the German of Dr. C. Deite, A. 
Engelhardt, Dr. C. Schaedler and others; with additions and lists 
of American Patents relating to these subjects. By Wm. T. Brannt. 
Illustrated by 163 engravings. 677 pages. 8vo. . . #7.50 

BRANNT. — A Practical Treatise on the Raw Materials and the 
Distillation and Rectification of Alcohol, and the Prepara- 
tion of Alcoholic Liquors, Liqueurs, Cordials, Bitters, etc.: 
Edited chiefly from the German of Dr. K. Stammer, Dr. F. Eisner, 
and E. Schubert. By Wm. T. Brannt. Illustrated by thirty-one 
engravings. 121110. ....... $2.50 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 



BRANNT-WAHL.-The Techno-Chemical Receipt Book: 

Containing several thousand Receipts covering the latest, most »flj 
portant, and most useful discoveries in Chemical Technology, anc 
their Practical Application in the Arts and the Industries. Editec 
chiefly from the German of Drs. Winckler, Eisner, Heintze, Mier 
zinski, Jacobsen, Roller, and Heinzerling, with additions by Wm. 1. 
Brannt and Wm. H. Wahl, Ph. D. Illustrated by 78 engravings, 
israo. 495 pages . . . $2.00 

BROWN. — Five Hundred and Seven Mechanical Movements: 
Embracing all those which are most important in Dynamics, Hy- 
draulics, Hydrostatics, Pneumatics, Steam-Engines, Mill and other 
Gearing, Presses, Horology and Miscellaneous Machinery; and in- 
cluding many movements never before published, and several of 
which have only recently come into use. By Henry T. Brown, 
l2mo. .......... $1.00 

BUCKMASTER.— The Elements of Mechanical Physics : 
By J. C. Buckmaster. Illustrated with numerous engravings. 
i2tno $1.00 

BULLOCK.— The American Cottage Builder : 

A Series of Designs, Plans and Specifications, from $200 to $20,000, 
for Homes for the People ; together with Warming, Ventilation, 
Drainage, Painting and Landscape Gardening. By John Bullock, 
Architect and Editor of " The Rudiments of Architecture and 
Building," etc., etc. Illustrated by 75 engravings. 8vo. $3.00 

BULLOCK. — The Rudiments of Architecture and Building : 
For the use of Architects, Builders, Draughtsmen, Machinists, En- 
gineers and Mechanics. Edited by John Bullock, author of " The 
American Cottage Builder." Illustrated by 250 Engravings. 8vo. $3.00 

BURGH. — Practical Rules for the Proportions of Modern 
Engines and Boilers for Land and Marine Purposes. 
By N. P. Burgh, Engineer. i2mo. .... $1.50 

BYLES. — Sophisms of Free Trade and Popular Political 

Economy Examined. 

By a Barrister (Sir John Barnard Byles, Judge of Common 

Pleas). From the Ninth English Edition, as published by the 

Manchester Reciprocity Association. i2mo. . . . $1.25 

BOWMAN.— The Structure of the Wool Fibre in its Relation 
to the Use of Wool for Technical Purposes : 
Being the substance, with additions, of Five Lectures, deliverea at 
the request of the Council, to the members of the Bradford Technical 
College, and the Society of Dyers and Colorists. By F. H. Bow- 
man, D. Sc, F. R. S. E., F. L. S. Illustrated by 32 engravings. 
8vo $6.50 

BYRNE. — Hand-Book for the Artisan, Mechanic, and Engi- 
neer: 
Comprising the Grinding and Sharpening of Cutting Tools, Abia-.ve 
Processes, Lapidary Work, Gem and Glass Engraving, Varnishing 
and Lackering, Apparatus, Materials and Processes for Grinding and 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 



Polishing, etc. By Oliver Byrne. Illustrated by 185 wood en- 
gravings. 8vo. ........ $5.00 

BYRNE. — Pocket-Book for Railroad and Civil Engineers: 

Containing New, Exact and Concise Methods for Laying out Railroad 
Curves, Switches, Frog Angles and Crossings; the Staking out of 
work ; Levelling ; the Calculation of Cuttings ; Embankments ; Earth- 
work, etc. By Oliver Byrne. i8mo., full bound, pocket-book 
form #1.75 

BYRNE. — The Practical Metal-Worker's Assistant : t 

Comprising Metallurgic Chemistry ; the Arts of Working all Metals 
and Alloys; Forging of Iron and Steel; Hardening and Tempering; 
Melting and Mixing; Casting and Founding ; Works in Sheet Metal; 
the Processes Dependent on the Ductility of the Metals; Soldering; 
and the most Improved Processes and Tools employed by Metal- 
workers. With the Application of the Art of Electro-Metallurgy to 
Manufacturing Processes ; collected from Original Sources, and from 
the works of Holtzapffel, Bergeron, Leupold, Plumier, Napier, 
Scoffern, Clay, Fairbairn and others. By Oliver Byrne. A new, 
revised and improved edition, to which is added an Appendix, con- 
taining The Manufacture of Russian Sheet-Iron. By John Percy, 
M. D., F. R. S. The Manufacture of Malleable Iron Castings, and 
Improvements in Bessemer Steel. By A. A. Fesquet, Chemist and 
Engineer. With over Six Hundred Engravings, Illustrating every 
Branch of the Subject. 8vo $5-O0 

BYRNE.— The Practical Model Calculator: 

For the Engineer, Mechanic, Manufacturer of Engine Work, Naval 
Architect, Miner and Millwright. By Oliver Byrne. 8vo., nearly 
600 pages ......... $3-00 

CABINET MAKER'S ALBUM OF FURNITURES 
Comprising a Collection of Designs for various Styles of Furniture. 
Illustrated by Forty-eight Large and Beautifully Engraved Plates, 
Oblong, 8vo #2.00 

CALLINGHAM. — Sign Writing and Glass Embossing: 

A Complete Practical Illustrated Manual of the Art. By James 
Callingham. i2mo $i-5o 

CAM PIN. — A Practical Treatise on Mechanical Engineering: 
Comprising Metallurgy, Moulding, Casting, Forging, Tools, Work- 
shop Machinery, Mechanical Manipulation, Manufacture of Steam* 
Engines, etc. With an Appendix on the Analysis of Iron and Iron 
Ores. By Francis Campin, C. E. To which are added, Observations 
on the Construction of Steam Boilers, and Remarks upon Furnaces 
used for Smoke Prevention ; with a Chapter on Explosions. By R. 
Armstrong, C. E., and John Bourne. Rules for Calculating th« 
Change Wheels for Screws on a Turning Lathe, and for a Wheel* 
cutting Machine. By J. La Nicca. Management of Steel, Includ- 
ing Forging, Hardening, Tempering, Annealing, Shrinking and 
Expansion ; and the Case-hardening of Iron. By G. Ede. 8vo. 
Illustrated with twenty-nine plates and 100 wood engravings $5.00 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 



CAREY.— A Memoir of Henry C. Carey. 

By Dr. Wm. Elder. With a portrait. 8vo., cloth . . 75 

CAREY.— The Works of Henry C. Carey : 

Harmony of Interests : Agricultural, Manufacturing and Commer. 
cial. 8vo. ..... $1.25 

Manual of Social Science. Condensed from Carey's " Principles 
of Social Science." By Kate McKean. i vol. i2mo. . #2.00 
Miscellaneous Works. With a Portrait. 2 vols. 8vo. $10.00 

Past, Present and Future. 8vo $2.50 

Principles of Social Science. 3 volumes, 8vo. . . $7.50 
The Slave-Trade, Domestic and Foreign; Why it Exists, and 
How it may be Extinguished (1853). 8vo. . . . $2.00 
The Unity of Law : As Exhibited in the Relations of Physical, 
Social, Mental and Moral Science (1872). 8vo. . . $2.50 

CLARK. — Tramways, their Construction and Working : 

Embracing a Comprehensive History of the System. With an ex' 
haustive analysis of the various modes of traction, including horse- 
power, steam, heated water and compressed air; a description of the 
varieties of Rolling stock, and ample details of cost and working ex- 
penses. By D. Kinnear Clark. Illustrated by over 200 wood 
engravings, and thirteen folding plates. I vol. 8vo. . $9.00 

COLBURN.— The Locomotive Engine : 

Including a Description of its Structure, Rules for Estimating its 
Capabilities, and Practical Observations on its Construction and Man- 
agement. By Zerah Colburn. Illustrated. i2mo. . $1.00 

COLLENS.— The Eden of Labor; or, the Christian Wtopia. 
By T. Wharton Collens, author, of " Humanics," " The History 
of Charity," etc. i2mo. Paper cover, $1.00; Cloth . $1.25 

COOLEY. — A Complete Practical Treatise on Perfumery: 
Being a Hand-book of Perfumes, Cosmetics and other Toilet Articles. 
With a Comprehensive Collection of Formulae. By Arnold J« 
Cooley. 121110 $1.5© 

COOPER. — A Treatise on the use of Belting for the Trans, 
mission of Power. 
With numerous illustrations of approved and actual methods of ar- 
ranging Main Driving and Quarter Twist Belts, and of Belt Fasten 
ings. Examples and Rules in great number for exhibiting and cal- 
culating the size and driving power of Belts. Plain, Particular and 
Practical Directions for the Treatment, Care and Management o r 
Belts. Descriptions of many varieties of Beltings, together with 
chapters on the Transmission of Power by Ropes; by Iron and 
Wood Frictional Gearing; on the Strength of Belting Leather; and 
on the Experimental Investigations of Morin, Briggs, and others. By 
John H. Cooper, M. E. 8vo $3.50 

CRAIK. — The Practical American Millwright and Miller. 

By David Craik, Millwright. Illustrated by numerous wood en- 
gravings and two folding plates. 8vo $3.50 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 9 

CROSS. — The Cotton Yarn Spinner : 

Showing how the Preparation should be arranged for Different 
Counts of Yarns by a System more uniform than has hitherto been 
practiced; by having a Standard Schedule from which we make all 
our Changes. By Richard Cross. 122 pp. i2mo. . 75 

CRISTIANI. — A Technical Treatise on Soap and Candles: 

With a Glance at the Industry of Eats and Oils. By R. S. Cris- 
tiani, Chemist. Author of " Perfumery and Kindred Arts." Illus- 
trated by 176 engravings. 581 pages, 8vo. . . . #15.00 

COAL AND METAL MINERS' POCKET BOOK: 

Of Principles, Rules, Formulae, and Tables, Specially Compiled 
and Prepared for the Convenient Use of Mine Officials, Mining En- 
gineers, and Students preparing themselves for Certificates of Compe- 
tency as Mine Inspectors or Mine Foremen. Revised and Enlarged 
edition. Illustrated, 565 pages, small l2mo., cloth. . #2.00 

Pocket book form, flexible leather with flap . . #2.75 

DAVIDSON. — A Practical Manual of House Painting, Grain- 
ing, Marbling, and Sign- Writing: 
Containing full information on the processes of House Painting in 
Oil and Distemper, the Formation of Letters and Practice of Sign- 
Writing, the Principles of Decorative Art, a Course of Elementary 
Drawing for House Painters, Writers, etc., and a Collection of Useful 
Receipts. With nine colored illustrations of Woods and Marbles, 
and numerous wood engravings. By Ellis A. Davidson. i2mo. 

#3-oo 

DAVIES. — A Treatise on Earthy and Other Minerals and 
Mining: 
By D. C. Davies, F. G. S., Mining Engineer, etc. Illustrated by 
76 Engravings. l2mo. ...... . #5.00 

DAVIES. — A Treatise on Metalliferous Minerals and Mining: 
By D. C. Davies, F. G. S., Mining Engineer, Examiner of Mines, 
Quarries and Collieries. Illustrated by 148 engravings of Geological 
Formations, Mining Operations and Machinery, drawn from the 
practice of all parts of the world. Fifth Edition, thoroughly Revised 
and much Enlarged by his son, E. Henry Davies. i2mo., 524 
pages . #5.00 

DAVIES. — A Treatise on Slate and Slate Quarrying: 

Scientific, Practical and Commercial. By D. C. Davies, F. G. S., 
Mining Engineer, etc. With numerous illustrations and folding 
plates. i2mo. ........ #2.00 

DAVIS. — A Practical Treatise on the Manufacture of Brick, 

Tiles and Terra- Cotta : 

Including Stiff Clay, Dry Clay, Hand Made, Pressed or Front, and 

Roadway Paving Brick, Enamelled Brick, with Glazes and Colors, 

Fire Brick and Blocks, Silica Brick, Carbon Brick, Glass Pots, Re- 



io HENRY CAREY BAIRD & CO.'S CATALOGUE. 



torts, Architectural Terra-Cotta, Sewer Pipe, Drain Tile, Glazed and 
Unglazed Roofing Tile, Art Tile, Mosaics, and Imitation of Intarsia 
or Inlaid Surfaces. Comprising every product of Clay employed in 
Architecture, Engineering, and the Blast Furnace. With a Detailed 
Description of the Different Clays employed, the Most Modern 
Machinery, Tools, and Kilns used, and the Processes for Handling, 
Disintegrating, Tempering, and Moulding the Clay into Shape, Dry- 
ing, Setting, and Burning. By Charles Thomas Davis. Third Edi- 
tion. Revised and in great part rewritten. Illustrated by 261 
engravings. 662 pages . . . . . . $5.00 

DAVIS. — A Treatise on Steam-Boiler Incrustation and Meth- 
ods for Preventing Corrosion and the Formation of Scale : 
By Charles T. Davis. Illustrated by 65 engravings. 8vo. $1.50 

DAVIS. — The Manufacture of Paper: 

Being a Description of the various Processes for the Fabrication, 
Coloring and Finishing of every kind of Paper, Including the Dif- 
ferent Raw Materials and the Methods for Determining their Values, 
the Tools, Machines and Practical Details connected with an intelli- 
gent and a profitable prosecution of the art, with special reference to 
the best American Practice. To which are added a History of Pa- 
per, complete Lists of Paper-Making Materials, List of American 
Machines, Tools and Processes used in treating the Raw Materials, 
and in Making, Coloring and Finishing Paper. By Charles T. 
Davis. Illustrated by 156 engravings. 608 pages, 8vo. $6.00 

DAVIS. — The Manufacture of Leather: 

Being a description of all of tl Processes for the Tanning, Tawing, 
Currying, Finishing and Dyeing of every kind of Leather ; including 
the various Raw Materials and the Methods for Determining their 
Values; the Tools, Machines, and all Details of Importance con- 
nected with an Intelligent and Profitable Prosecution of the Art, with 
Special Reference to the Best American Practice. To which are 
added Complete Lists of all American Patents for Materials, Pro- 
cesses, Tools, and Machines for Tanning, Currying, etc. By Charles 
Thomas Davis. Illustrated by 302 engravings and 12 Samples of 
Dyed Leathers. One vol., 8vo., 824 pages . . . $25.00 

DAWIDOWSKY— BRANNT.— A Practical Treatise on the 

Raw Materials and Fabrication of Glue, Gelatine, Gelatine 

Veneers and Foils, Isinglass, Cements, Pastes, Mucilages, 

etc. : 

Eased upon Actual Experience. By F. Dawidowsky, Technical 

Chemist. Translated from the German, with extensive additions, 

including a description of the most Recent American Processes, by 

William T. Brannt, Graduate of the Royal Agricultural College 

of Eldena, Prussia. 35 Engravings. i2mo. . . . $2.50 

DE GRAFF.— The Geometrical. Stair-Builders' Guide: 
Being a Plain Practical System of Hand-Railing, embracing all its 
necessary Details, and Geometrically Illustrated by twenty-two Steel 
Engravings ; together with the use of the most approved principles 
of Practical Geometry. By Simon De Graff, Architect. <.to. 

$2.50 



HENRY CAREY BAIRD & CO.'S CATALOGUE. it 

DE KONINCK— DIETZ.— A Practical Manual of Chemical 
Analysis and Assaying : 
As applied to the Manufacture of Iron from its Ores, and to Cast Iron, 
Wrought Iron, and Steel, as found in Commerce. By L. L. Dh 
Koninck, Dr. Sc, and E. Dietz, Engineer. Edited with Notes, by 
Robert Mallet, F. R. S., F. S. G., M. I. C. E., etc. American 
Edition, Edited with Notes and an Appendix on Iron Ores, by A. A. 
Fesquet, Chemist and Engineer. i2mo. . . . $1.50 

DUNCAN. — Practical Surveyor's Guide: 

Containing the necessary information to make any person of corm 
mon capacity, a finished land surveyor without the aid of a teacher 
By Andrew Duncan. Revised. 72 engravings, 214 pp. izmo. #1.50 

DUPLAIS. — A Treatise on the Manufacture and Distillation 
of Alcoholic Liquors : 
Comprising Accurate and Complete Details in Regard to Alcohol 
from Wine, Molasses, Beets, Grain, Rice, Potatoes, Sorghum, Aspho 
del, Fruits, etc. ; with the Distillation and Rectification of Brandy 
Whiskey, Rum, Gin, Swiss Absinthe, etc., the Prepar?tion of Aro- 
matic Waters, Volatile Oils or Essences, Sugars, Syrups, Aromatic 
Tinctures, Liqueurs, Cordial Wines, Effervescing Wines, etc., the 
Ageing of Brandy and the improvement of Spirits, with Copious 
Directions and Tables for Testing and Reducing Spirituous Liquors, 
etc., etc. Translated and Edited from the French of MM. Duplais, 
Aine et Jeune. By M. McKennie, M. D. To which are added the 
United States Internal Revenue Regulations for the Assessment and 
Collection of Taxes on Distilled Spirits. Illustrated by fourteen 
folding plates and several wood engravings. 743 pp. 8vo. |io oo 

DUSSAUCE.— Practical Treatise on the Fabrication of Matches, 
Gun Cotton, and Fulminating Powder. 
By Professor H. Dussauce. i2mo. . . . . $3 oo 

DYER AND COLOR-MAKER'S COMPANION: 

Containing upwards of two hundred Receipts for making Colors, on 
the most approved principles, for all the various styles and fabrics now 
in existence; with the Scouring Process, and plain Directions for 
Preparing, Washing-off, and Finishing the Goods. i2mo. $1.00 

EDWARDS. — A Catechism of the Marine Steam-Engine, 
For the use of Engineers, Firemen, and Mechanics. A Practical 
Work for Practical Men. By Emory Edwards, Mechanical Engi- 
neer. Illustrated by sixty-three Engravings, including examples of 
the most modern Engines. Third edition, thoroughly revised, with 
much additional matter. 1 2 mo. 414 pages . . . $2 00 

EDWARDS. — Modern American Locomotive Engines, 
Their Design, Construction and Management. By EMORY Edwards 
Illustrated i2mo. ........ $2.00 

EDWARDS.— The American Steam Engineer: 

Theoretical and Practical, with examples of the latest and most ap- 
proved American practice in the design and construction of Steam 
Engines and Boilers. For the use of engineers, machinists, boiler- 
makers, and engineering students. By Emory Edwards. Fully 
illustrated, 419 pages. i2mo. , $2.50 



12 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

EDWARDS. — Modern American Marine Engines, Boilers, and 
Screw Propellers, 

Their Design and Construction. Showing the Present Practice ot 
the most Eminent Engineers and Marine Engine Builders in the 
United States. Illustrated by 30 large and elaborate plates. 4x0. $5.00 
tD WARDS.— The Practical Steam Engineer's Guide 
In the Design, Construction, and Management of American Stationary, 
Portable, and Steam Fire- Engines, Steam Pumps, Boilers, Injectors, 
Governors, Indicators, Pistons and Rings, Safety Valves and Steam 
Gauges. For the use of Engineers, Firemen, and Steam Users. By 
Emory Edwards. Illustrated by 119 engravings. 4.20 pages. 
i2mu .... $2 50 

EISSLER.— The Metallurgy of Gold : 

A Practical Treatise 011 the Metallurgical Treatment of Gold-Bear, 
ing Ores, including the Processes of Concentration and Chlorination, 
and the Assaying, Melting, and Refining of Gold. By M. Eissler. 
With 132 Illustrations. l2mo. $5.00 

EISSLER.— The Metallurgy of Silver : 

A Practical Treatise on the Amalgamation, Roasting, and Lixiviation 
of Silver Ores, including the Assaying, Melting, and Refining of 
Silver Bullion. By M. Eissler. 124 Illustrations. 336 pp. 
i2tno $4.25 

ELDER. — Conversations on the Principal Subjects of Political 
Economy. 
By Dr. William Elder. 8vo. . ... . . #2.50 

ELDER.— Questions of the Day, 

Economic and Social. By Dr. William Elder. 8vo. . $3.00 

ERNI. — Mineralogy Simplified. 
Easy Methods of Determining and Classifying Minerals, including 
Ores, by means of the Blowpipe, and by Humid Chemical Analysis, 
based on Professor von Kobell's Tables for the Determination of 
Minerals, with an Introduction to Modern Chemistry. By Henry 
Erni, A.M., M.D., Professor of Chemistry. Second Edition, rewritten, 
enlarged and improved. i2mo. ..... #3.00 

FAIRBAIRN.— The Principles of Mechanism and Machinery 
of Transmission • 
Comprising the Principles of Mechanism, Wheels, and Pulleys, 
Strength and Proportions of Shafts, Coupling of Shafts, and Engag- 
ing and Disengaging Gear. By Sir William Fairbairn, Bart. 
C. E. Beautifully illustrated by over 150 wood-cuts. In one 
volume, i2mo. .....•••• $2.50 

FLEMING.— Narrow Gauge Railways in America. 

A Sketch of their Rise, Progress, and Success. Valuable Statistics 
as to Grades, Curves, Weight of'Rail, Locomotives, Cars, etc. By 
Howard Fleming. Illustrated, 8vo $1 00 

FORSYTH.— Book of Designs for Headstones, Mural, and 
other Monuments : 
Containing 78 Designs. By James Forsyth. With an Introduction 
by Charles Boutell, M. A. 4 to., cloth . . ■ $& 00 



HENRY CAREY BAIRD & CO.'S CATALOGUE. *3 



FRANKEL— HUTTER.— A Practical Treatise on the Manu- 
facture of Starch, Glucose, Starch-Sugar, and Dextrine: 
Based on the German of Ladislaus Von Wagner, Professor in the 
Royal Technical High School, Buda-Pest, Hungary, and other 
authorities. By Julius Frankel, Graduate of the Polytechnic 
School of Hanover. Edited by Robert Hutter, Chemist, Practicai 
Manufacturer of Starch-Sugar. Illustrated by 58 engravings, cover- 
ing every branch of the subject, including examples of the most 
Recent and Best American Machinery. 8vo., 344 pp. . $3.50 

GARDNER.— The Painter's Encyclopaedia: 
Containing Definitions of all Important Words in the Art of Plain 
and Artistic Painting, with Details of Practice in Coach, Carriage, 
Railway Car, House, Sign, and Ornamental Painting, including 
Graining, Marbling, Staining, Varnishing, Polishing, Lettering, 
Stenciling, Gilding, Bronzing, etc. By Franklin B. Gardner. 
158 Illustrations. i2mo. 427 pp. ..... $2.00 

GARDNER.— Everybody's Paint Book: 

A Complete Guide to the Art of Outdoor and Indoor Painting, De- 
signed for the Special Use of those who wish to do their own work, 
and consisting of Practical Lessons in Plain Painting, Varnishing, 
Polishing, Staining, Ppprr Hanging, Kalsomining, etc., as well as 
Directions for Renovating Furniture, and Hints on Artistic Work for 
Home Decoration. 38 Illustrations. i2mo., 183 pp. . $1.00 

SEE.— The Goldsmith's Handbook : 

Containing full instructions for the Alloying and Working -of Gold, 
including the Art of Alloying, Melting, Reducing, Coloring, Col 
lecting, and Refining; the Processes of Manipulation, Recovery of 
Waste; Chemical and Physical Properties of Gold; with a New- 
System of Mixing its Alloys ; Solders, Enamels, and other Useful 
Rules and Recipes. By George E. Gee. i2mo. „ . $1-75 

GEE.— The Silversmith's Handbook : 

Containing full instructions for the Alloying and Working of Silver, 
including the different modes of Refining and Melting the Metal; its 
Solders ; the Preparation of Imitation Alloys ; Methods of Manipula- 
tion; Prevention of Waste ; Instructions for Improving and Finishing 
the Surface of the Work ; together with other Useful Information and 
Memoranda. By George E. Gee. Illustrated. 121110. $1-75 

GOTHIC ALBUM FOR CABINET-MAKERS: 

Designs for Gothic Furniture. Twenty-three plates. Oblong $2.00 

GRANT. — A Handbook on the Teeth of Gears : 
Their Curves, Properties, and Practical Construction. By George 
B. Grant. Illustrated. Third Edition, enlarged. 8vo. $1.00 

GREENWOOD.— Steel and Iron: 

Comprising the Practice and Theory of the Several Methods Pur- 
sued in their Manufacture, and of their Treatment in the Rolling- 
Mills, the Forge, and the Foundry. By William Henry Green- 
WOOD s F. C. S. With 97 Diagrams, 536 pages. i2mo. $2.00 



14 HENRY CAREY BAIRD & CO.'S CATALOGUE. 



GREGORY. — Mathematics for Practical Men : 

Adapted to the Pursuits of Surveyors, Architects, Mechanics, and 
Civil Engineers. By Olinthus Gregory. 8vo., plates $3.00 
GRISWOLD. — Railroad Engineer's Pocket Companion for th< 
Field : 

Comprising Rules for Calculating Deflection Distances and Angles, 
Tangential Distances and Angles, and all Necessary Tables for En 
gineers; also the Art of Levelling from Preliminary Survey to the 
Construction of Railroads, intended Expressly for the Young En- 
gineer, together with Numerous Valuable Rules and Examples. By 
W. Griswold. i2mo., tucks $*-75 

GRUNER. — Studies of Blast Furnace Phenomena: 

By M. L. Gruner, President of the General Council of Mines oS 
France, and lately Professor of Metallurgy at the Ecole des Mines. 
Translated, with the author's sanction, with an Appendix, by L. D. 
B. Gordon, F. R. S. E., F. G. S. 8vo. . . . $2.50 

Hand-Book of Useful Tables for the Lumberman, Farmei and 
Mechanic : 
Containing Accurate Tables of Logs Reduced to Inch Board Meas. 
ure, Plank, Scantling and Timber Measure; Wages and Rent, by 
Week or Month; Capacity of Granaries, Bins and Cisterns; Land 
Measure, Interest Tables, with Directions for Finding the Interest on 
any sum at 4, 5, 6, 7 and 8 per cent., and many other Useful Tables. 
32 mo., boards. 186 pages .25 

HASERICK.— The Secrets of the Art of Dyeing Wool, Cotton, 
and Linen, 
Including Bleaching and Coloring Wool and Cotton Hosiery and 
Random Yarns. A Treatise based on Economy and Practice. By 
E. C. Haserick. Illustrated by 323 Dyed Patterns of the Yami 
or Fabrics. 8vo. ........ $7- 5° 

HATS AND FELTING: 

A Practical Treatise on their Manufacture. By a Practical Platter, 
Illustrated by Drawings of Machinery, etc. 8vo. . . $1.25 

HOFFER. — A Practical Treatise on Caoutchouc and Gutta 
Percha, 
Comprising the Properties of the Raw Materials, and the manner or". 
Mixing and Working them ; with the Fabrication of Vulcanized and 
Hard Rubbers, Caoutchouc and Gutta Per.cha Compositions, Water- 
proof Substances, Elastic Tissues, the Utilization of Waste, etc., eii_, 
From the German of Raimund Hoffer. By W. T. Eraknt. 
Illustrated i2mo $2. 5c 

HAUPT. — Street Railway Motors: 

With Descriptions and Cost of Plants and Operation of the Various 
Systems now in Use. i2mo. ..... $1-75 



HENRY CAREY BAIRD & CO.'S CATALOGUE. it; 

HAUPT— RHAWN.— A Move for Better Roads: 

Essays on Road-making and Maintenance and Road Laws, for 
which Prizes or Honorable Mention were Awarded through the 
University of Pennsylvania by a Committee of Citizens of Philadel- 
phia, with a Synopsis of other Contributions and a Review by the 
Secretary, Lewis M. Haupt, A. M., C. E. ; also an Introduction by 
William H. Rhawn, Chairman of the Committee. 319 pages. 
8vo. $2.oa 

HUGHES. — American Miller and Millwright's Assistant: 
By William Carter Hughes. i2mo #1.50 

HULME. — Worked Examination Questions in Plane Geomet- 
rical Drawing : 
For the Use of Candidates for the Royal Military Academy, Wool- 
wich; the Royal Military College, Sandhurst ; the Indian Civil En- 
gineering College, Cooper's Hdl ; Indian Public Works and Tele- 
graph Departments ; Royal Marine Litiht Infantry; the Oxford and 
Cambridge Local Examinations, etc. By F. Edward Hulme, F. L. 
S., F. S. A., Art-Master Marlborough College. Illustrated by 300 
examples. Small quartc ...... <> $2.50- 

JERVIS.— Railroad Property: 

A Treatise on the Construction and Management of Railways', 
designed to afford useful knowledge, in the popular style, to the 
holders of this class of property; as well as Railway Managers, Offi- 
cers, and Agents. By John B. Jervis, late Civil Engineer of the 
Hudson River Railroad, Croton Aqueduct, etc. i2mo., cloth $2.oc 

KEENE.-A Hand-Book of Practical Gauging: 

For the Use of Beginners, to which is added a Chapter on Distilla- 
tion, describing the process in operation at the Custom-House for 
ascertaining the Strength of Wines. By James B. Keene, of H. M. 
Customs. 8vo. $1.25 

KELLEY. — Speeches, Addresses, and Letters on Industrial and 
Financial Questions : 
By Hon. William D. Kelley, M. C. 544 pages, 8vo. . #2.50 

KELLOGG. — A New Monetary System : 

The only means of Securing the respective Rights of Labor and 
Property, and of Protecting the Public from Financial Revulsions. 
By Edward Kellogg. Revised from his work on "Labor and 
other Capital." With numerous additions from his manuscript. 
Edited by Mary Kellogg Putnam. Fifth edition. To which is 
added a Biographical Sketch of the Author. One volume, i2mo. 
Paper cover ......... $1.00 

Bound in cloth I.25 

KEMLO. — Watch- Repairer's Hand-Book : 
Being a Complete Guide to the Young Beginner, in Taking Apart, 
Putting Together, and Thoroughly Cleaning the English Lever and 
other Foreign Watches, and all American Watches. By F. Kemlo, 
"Sracticai Watchmaker. With Illustrations. i2mo. . $1.25 



16 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

KENTISH. — A Treatise on a Box of Instruments, 

And the Slide Rule ; with the Theory of Trigonometry and Loga 
rithms, including Practical Geometry, Surveying, Measuring of Tim. 
ber, Cask and Malt Gauging, Heights, and Distances. By Thoma* 
Kentish. In one volume. i2mo. .... $1.25 

KERL. — The Assayer's Manual: 

An Abridged Treatise on the Docimastic Examination of Ores, and 
Furnace and other Artificial Products. By Bruno Kerl, Professor 
in the Royal School of Mines. Translated from the German by 
William T. Brannt. Second American edition, edited with Ex- 
tensive Additions by F. LySwood Garrison, Member of the 
American Institute of Mining Engineers, etc. Illustrated by 87 en- 
gravings. 8vo. ........ $3-OC 

KICK. — Flour Manufacture. 

A Treatise on Milling Science and Practice. By Frederick Kick 
Imperial Regierungsrnth, Professor of Mechanical Technology in tht 
imperial German Polytechnic Institute, Prague. Translated from 
the second enlarged and revised edition with supplement by H. H. 
P. Powles, Assoc. Memb Institution of Civil Engineers. Illustrated 
with 28 Plains, and 167 Wood-cuts. 367 pages. 8vo. . $10.00 

KINGZETT. — The History, Products, and Processes of the 
Alkali Trade : 
Including the most Recent Improvements. By Charles Thomas 
Kingzett, Consulting Chemist. With 23 illustrations. 8vo. $2.50 

KIRK.— The Founding of Metals : 

A Practical Treatise on the Melting of Iron, with a Description of the 
Founding of Alloys; also, of all the Metals and Mineral Substances 
used in the Art of Founding. Collected from original sources. By 
Edward Kirk, Practical Foundryman and Chemist. Illustrated, 
Third edition. 8vo $2.50 

LANDRIN.— A Treatise on Steel : 
Comprising its Theory, Metallurgy, Properties, Practical Working, 
and Use. By M. H. C. Landrin, Jr., Civil Engineer. Translated 
from the French, with Notes, by A. A. Fesquet, Chemist and En 
gineer. With an Appendix on the Bessemer and the Martin Pro- 
^«ses for Manufacturing Steel, from the Report of Abram S. Hewitt 
United States Commissioner to the Universal Exposition, Paris, 1867. 
I2mn. . . ■ $3- oc 

LANGBEIN.— A Complete Treatise on the Electro-Deposition 
of Metals : 
Translated from the German, with Additions, by Wm. T. Brannt. 
125 illustrations. 8vo. ....... $4.00 

LARDNER.- The Steam-Engine : 

For the Use of Beginners. Illustrated. l2mo. 75 

LEHNER. — The Manufacture of Ink: 
Comprising the Raw Materials, and the Preparation df Waiting, 
Copying and Hektograph Inks, Safety Inks, Ink Extracts and Pow- 
ders, etc. Translated from the German of SlGMUND Lehner, with 
additions by William T. Brannt. Illustrated. i2mo. $2:00 



HENRY CARE\ BAIRD & CO.'S CATALOGUE. 17 

LARKIN. — The Practical Brass and Iron Founder's Guide: 
A Concise Treatise on Brass Founding, Moulding, the Metals and 
their Alloys, etc. ; to which are added Recent Improvements in the 
Manufacture of Iron, Steel by the Bessemer Process, etc., etc. By 
Tames Larkin, late Conductor of the Brass Foundry Department in 
Reany, Neafie & Co.'s Penn Works, Philadelphia. New edition, 
revised, with extensive additions. i2mo. . . . $2.50 

LEROUX. — A Practical Treatise on the Manufacture of 
Worsteds and Carded Yarns : 
Comprising Practical Mechanics, with Rules and Calculations applied 
to Spinning; Sorting, Cleaning, and Scouring Wools; the English 
and French Methods of Combing, Drawing, and Spinning Worsteds, 
and Manufacturing Carded Yarns. Translated from the French of 
Charles Leroux, Mechanical Engineer and Superintendent of a 
9pinning-Mill, by Horatio Paine, M. D., and A. A. Fesquet, 
Chemist and Engineer. Illustrated by twelve large Plates. To which 
is added an Appendix, containing Extracts from the Reports of the 
International Jury, and of the Artisans selected by the Commutes 
appointed by the Council of the Society of Arts, London, on Woolen 
and Worsted Machinery and Fabrics, as exhibited in the Paris TJni* 
versa! Exposition, 1867. 8vo. . . . . . $5.00 

LEFFEL.— The Construction of Mill-Dams : 
Comprising also the Building of Race and Reservoir Embankments 
and Head-Gates, the Measurement of Streams, Gauging of Water 
Supply, etc. By James Leffel & Co. Illustrated by 58 engravings. 
8vo. $2.50 

LESLIE. — Complete Cookery: 
Directions for Cookery in its Various Branches. By Miss Leslie. 
Sixtieth thonsand. Thoroughly revised, with the addition of New 
Receipts. i2mo. ........ $1.50 

LE VAN. — The Steam Engine and the Indicator: 

Their Origin and Progressive Development ; including the Most 
Recent Examples of Steam and Gas Motors, together with the Indi- 
cator, its Principles, its Utility, and its Application. By William 
Barnet Le Van. Illustrated by 205 Engravings, chiefly of Indi- 
cator-Cards. 469 pp. 8vo. ...... $4.00 

LIEBER.— Assayer's Guide ; 
Or, Practical Directions to Assayers, Miners, and Smelters, for the 
Tests and Assays, by Heat and by Wet Processes, for the Ores of all 
the principal Metals, of Gold and Silver Coins and Alloys, and of 
Coal, etc. By Oscar M. Lieber. Revised. 283 pp. i2mo. $1.50 

Lockwood's Dictionary of Terms : 

Used in the Practice of Mechanical Engineering, embracing those 
Current in the Drawing Office, Pattern Shop, Foundry, Fitting, Turn- 
ing, Smith's and Boiler Shops, etc., etc., comprising upwards of Six- 
Thousand Definitions. Edited by a Foreman Pattern Maker, author 
of " Pattern Making." 417 pp. i2mo. - . . $3.00 



i8 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

LUKIN.— Amongst Machines : 

Embracing Descriptions of the various Mechanical Appliances used 
in the Manufacture of Wood, Metal, and other Substances. J2mo. 

LUKIN.— The Boy Engineers: 
What They Did, and How They Did It. With 30 plates. l8mo. 

LUKIN.— The Young Mechanic : 

Practical Carpentry. Containing Directions for the Use of all kinds 
af Tools, and for Construction of Steam-Engines and Mechanical 
Models, including the Art of Turning in Wood and Metal. By John 
Lukin, Author of " The Lathe and Its Uses," etc. Illustrated. 

I2IC0 #1.75 

MAIN and BROWN. — Questions on Subjects Connected with 

the Marine Steam-Engine : 

And Examination Papers; with Hints for their Solution. By 

Thomas J. Main, Professor of Mathematics, Royal Naval College, 

and Thomas Brown, Chief Engineer, R. N. i2mo., cloth . $1.00 

MAIN and BROWN. — The Indicator and Dynamometer: 
With their Practical Applications to the Steam-Engine. By THOMAS 
J. Main, M. A. F. R., Ass't S. Professor Royal Naval College, 
Portsmouth, and Thomas Brown, Assoc. Inst. C. E., Chief Engineer 
R. N., attached to the R. N. College. Illustrated. 8vo. . $1.00 

MAIN and BROWN.— The Marine Steam-Engine. 
By Thomas J. Main, F. R. Ass't S. Mathematical Professor at the 
Royal Naval College, Portsmouth, and Thomas Brown, Assoc. 
Inst. C. E., Chief Engineer R. N. Attached to the Royal Naval 
College. With numerous illustrations. 8vo. 

MAKINS.— A Manual of Metallurgy: 

By George Hogarth Makins. 100 engravings. Second edition 
rewritten and much enlarged. i2mo., 592 pages . . $3-oo 

MARTIN.— Screw-Cutting Tables, for the Use of Mechanica) 
Engineers : 
Showing the Proper Arrangement of Wheels for Cutting the Threads 
of Screws of any Required Pitch ; with a Table for Making the Uni- 
versal Gas-Pipe Thread and Taps. By W. A. Martin, Engineer. 
8vo. 5c 

MICHELL.— Mine Drainage: 
Being a Complete and Practical Treatise on Direct-Acting Under- 
ground Steam Pumping Machinery. With a Description of a large 
number of the best known Engines, their General Utility and the 
Special Sphere of their Action, the Mode of their Application, and 
their Merits compared with other Pumping Machinery. By Stephen 
Michell. Illustrated by 137 engravings. 8vo., 277 pages . $6.oo 

MOLESWORTH.— Pocket-Book of Useful Formulae and 
Memoranda for Civil and Mechanical Engineers. 
By Guilford L. Molesworth, Member of the Institution of Civi! 
Engineers, Chief Resident Engineer of the Ceylon Railway. Full- 
bound in Pocket-book form ...•■•• #l.ot 



iiENRY CAREY BA1KD <£ CU. ;a> CATALOGUE. 19 

MOORE. — The Universal Assistant and the Complete Me- 
chanic : 
Containing over one million Industrial Facts, Calculations, Receipts, 
Processes, Trades Secrets, Rules, Business Forms, Legal Items, Etc., 
in every occupation, from the Household to the Manufactory. By 
R. Moore. Illustrated by 500 Engravings. 12010. . $2.50 

MORRIS. — Easy Rules for the Measurement of Earthworks : 
By means of the Prismoidal Formula. Illustrated with Numerous 
Wood-Cuts, Problems, and Examples, and concluded by an Exten- 
sive Table for finding the Solidity in cubic yards from Mean Areas. 
The whole being adapted for convenient use by Engineers, Surveyors, 
Contractors, and others needing Correct Measurements of Earthwork. 

By Elwood Morris, C. E. 8vo #i-5a 

MAUCHLINE.— The Mine Foreman's Hand-Book 

Of Practical and Theoretical Information on the Opening, Venti- 
lating, and Working of Collieries. Questions and Answers on Prac- 
tical and Theoretical Coal Mining. Designed to Assist Students and 
Others in Passing Examinations for Mine Foremanships. By 
Robert Mauchline, Ex-Inspector of Mines. A New, Revised and 
Enlarged Edition. Illustrated by 114 engrarings. 8vo. 337 

pages #3.75 

NAPIER. — A System of Chemistry Applied to Dyeing. 
By James Napier, F. C. S. A New and Thoroughly Revised Edi« 
tion. Completely brought up to the present state of the Science, 
including the Chemistry of Coal Tar Colors, by A. A. Fesquet, 
Chemist and Engineer. With an Appendix on Dyeing and Ca«ico 
Printing, as shown at the Universal Exposition, Paris, 1867. Illus- 
trated. 8vo. 422 pages $3-5o 

NEVILLE.— Hydraulic Tables, Coefficients, and Formulse, foi 
finding the Discharge of Water from Orifices, Notches, 
Weirs, Pipes, and Rivers : 
Third Edition, with Additions, consisting of New Formulse for the 
Discharge from Tidal and Flood Sluices and Siphons ; general infor- 
mation on Rainfall, Catchment-Basins, Drainage, Sewerage, Wa;er 
Supply for Towns and Mill Power. By Tohn Neville, C. E. M R 
I. A. ; Fellow of the Royal Geological Society of Ireland. Thict 

»2«10 #5.50 

NEWBERY, — Gleanings from Ornamental Art of every 
style : 

Drawn from Examples in the British, South Kensington, Indian, 
Crystal Palace, and other Museums, the Exhibitions of 1851 and 
1862, and the best English and Foreign works. In a series of ioa 
. exquisitely drawn Plates, containing many hundred examples. Btf 
Robert Newbery. 4to. ...... $12.50 

NICHOLLS.— The Theoretical and Practical Boiler- Maker and 
Engineer's Reference Book: 

Containing a variety of Useful Information for Employers of Labor 
Foremen and Working Boiler- Makers. Iron, Copper, and Tinsmiths 



2 o HENRY CAREY BAIRD & CO.'S CATALOGUE. 

Draughtsmen, Engineers, the General Steam-using Public, and for the 
Use of Science Schools and Classes. By Samuel Nicholls. Illus- 
trated by sixteen plaies, l2mo. ..... $2.50 

NICHOLSON.— A Manual of the Art of Bookbinding: 

Containing full instructions in the different Branches of Forwarding, 
Gilding, and Finishing. Also, the Art of Marbling Book-edges and 
Paper. By James B. Nicholson. Illustrated. i2mo., cloth $2.25 

NICOLLS.— The Railway Builder: 
A Hand-Book for Estimating the Probable Cost of American Rail- 
way Construction and Equipment. By William J. Nicolls, Civil 
Engineer. Illustrated, full bound, pocket-book form . $2.00 

NORMANDY.— The Commercial Handbook of Chemical An- 
alysis : 
Or Practical Instructions for the Determination of the Intrinsic 01 
Commercial Value of Substances used in Manufactures, in Trades, 
and in the Arts. By A. Normandy. New Edition, Enlarged, and 
to a great extent rewritten. By Henry M. Noad, Ph.D., F.R.S., 
thick i2mo. ......... $5.00 

NORRIS. — A Handbook for Locomotive Engineers and Ma- 
chinists : 
Comprising the Proportions and Calculations for Constructing Loco- 
motives ; Manner of Setting Valves; Tables cf Squares, Cubes, Areas, 
etc., etc. By Septimus Norris, M. E. New edition. Illustrated, 
I2mo. $1.50 

NYSTRGM.— A New Treatise on Elements of Mechanics : 
Establishing Strict Precision in the Meaning of Dynamical Terms: 
accompanied with an Appendix on Duodenal Arithmetic and Me 
trology. By John W. Nystrom, C. E. Illustrated. 8vo. $2.00 

NYSTROM.— On Technological Education and the Construc- 
tion of Ships and Screw Propellers : 
For Naval and Marine Engineers. By John W. Nystrom, late 
Acting Chief Engineer, U. S. N. Second edition, revised, with addi- 
tional matter. Illustrated by seven engravings. i2mo. . $1.50 

O'NEILL. — A Dictionary of Dyeing and Calico Printing: 

Containing a brief account of all the Substances and Processes in 
use in the Art of Dyeing and Printing Textile Fabrics ; with Practical 
Receipts and Scientific Information. By Charles O'Neill, Analy- 
tical Chemist. To which is added an Essay on Coal Tar Colors and 
their application to Dyeing and Calico Printing. By A. A. Fesquet, 
Chemist and Engineer. With an appendix on Dyeing and Calico 
Printing, as shown at the Universal Exposition, Paris, 1867. 8vo., 
491 pages $3.50 

ORTON. — Underground Treasures-. 

How and Where to Find Them. . A Key for the Ready Determination 
of all the Useful Minerals within the United States. By James 
ORTON, A.M., Late Professor of Natural History in Vassar College, 
N. Y.; Cor. Mem. of the Academy of Natural Sciences, Philadelphia, 
and of the Lyceum of Natural History, New York ; author of the 
"Andes and the Amazon," etc. A New Edition, with Additions. 
Illustrated #1.50 



HENRY CAREY BAlRD & CO.'S CATALOGUE. 21 

OSBORN.— The Prospector's Field Book and Guide : 

In the Search for and the Easy Determination of Ores and Other 
Useful Minerals. By Prof. H. S. Osborn, LL. D., Author of 
"The Metallurgy of Iron and Steel;" "A Practical Manual of 
Minerals, Mines, and Mining." Illustrated by 44 Engravings. 
l2mo $l-5° 

OSBORN". — A Practical Manual of Minerals, Mines and Min- 
ing: 
Comprising the Physical Properties, Geologic Positions, Local Occur- 
rence and Associations of the Useful Minerals; their Methods of 
Chemical Analysis and Assay : together with Various Systems of 
Excavating and Timbering, Brick and Masonry Work, during Driv- 
ing, Lining, Bracing and other Operations, etc. "By Prof. H. S. 
Osborn, LL. D., Author of the " Metallurgy of Iron and Steel." 
Illustrated by 171 engravings from original drawings. 8vo. #4.50 

OVERMAN.— The Manufacture of Steel : 

Containing the Practice and Principles of Working and Making Steel. 
A Handbook for Blacksmiths and Workers in Steel and Iron, Wagon 
Makers, Die Sinkers, Cutlers, and Manufacturers of Files and Hard- 
ware, of Steel and Iron, and for Men of Science and Art. By 
Frederick Overman, Mining Engineer, Author of the " Manu- 
facture of Iron," etc. A new, enlarged, and revised Edition. By 
A. A. Fesqu£T, Chemist and Engineer. i2mo. . . $1.50 

OVERMAN.— The Moulder's and Founder's Pocket Guide : 
A Treatise on Moulding and Founding in Green-sand, Dry-sand, Loam, 
and Cement; the Moulding of Machine Frames, Mill-gear, Hollow- 
ware, Ornaments, Trinkets, Bells, and Statues; Description of Moulds 
for Iron, Bronze, Brass, and other Metals; Plaster of Paris, Sulphur, 
Wax, etc. ; the Construction of Melting Furnaces, the Melting and 
Founding of Metals ; the Composition of Alloys and their Nature, 
etc., etc. By Frederick Overman, M. E. A new Edition, to 
which is added a Supplement on Statuary and Ornamental Moulding, 
Ordnance, Malleable Iron Castings, etc. By A. A. Fesquet, Chem- 
ist and Engineer. Illustrated by 44 engravings. l2mo. . $2.00 

PAINTER, GILDER, AND VARNISHER'S COMPANION. 
Containing Rules and Regulations in everything relating to the AriJ 
of Painting, Gilding, Varnishing, Glass-Staining, Graining, Marbling, 
Sign- Writing, Gilding on Glass, and Coach Painting and Varnishing; 
Tests for the Detection of Adulterations in Oils, Colors, etc. ; and a 
Statement of the Diseases to which Painters are peculiarly liable, with 
the Simplest and Best Remedies. Sixteenth Edition. Revised, with 
an Appendix. Containing Colors and Coloring — Theoretical and 
Practical. Comprising descriptions of a great variety of Additional 
Pigments, their Qualities and Uses, to which are added, Dryers, and 
Modes and Operations of Painting, etc. Together with Chevreul*s 
Principles of Harmony and Contrast of Colors. l2mo. Cloth $l.$<i 

*>ALLETT. — The Miller's, Millwright's, and Engineer's Guide. 
By Henry Pallett. Illustrated. i2mo. . . • $2.o« 



22 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

PERCY. — The Manufacture of Russian Sheet-Iron. 

By John Percy, M. D., F. R. S., Lecturer on Metallurgy at the 
Royal School of Mines, and to The Advance Class of Artillery 
Officers at the Royal Artillery Institution, Woolwich; Author of 
" Metallurgy." With Illustrations. 8vo., paper . . 50 cts. 

PERKINS.— Gas and Ventilation : 

Practical Treatise on Gas and Ventilation. With Special Relation 
to Illuminating, Heating, and Cooking by Gas. Including Scientific 
Helps to Engineer-students and others. With Illustrated Diagrams. 
By E. E. Perkins. i2mo., cloth $1.25 

PERKINS AND STOWE.-A New Guide to the Sheet-iron 
and Boiler Plate Roller : 
Containing a Series of Tables showing the Weight of Slabs and Piles 
to Produce Boiler Plates, and of the Weight of Piles and the Sizes of 
Bars to produce Sheet-iron ; the Thickness of the Bar Gauge 
in decimals ; the Weight per foot, and the Thickness on the Bar or 
Wire Gauge of the fractional parts of an inch; the Weight per 
sheet, and the Thickness on the Wire Gauge of Sheet-iron of various 
dimensions to weigh 112 lbs. per bundle; and the conversion of 
Short Weight into Long Weight, and Long Weight into Short. 
Estimated and collected by G. H. Perkins and J. G. Stowe. $2.50 

POWELL— CHANCE— HARRIS,— The Principles of Glass 

Making. 

By Harry J. Powell, B. A. Together with Treatises on Crown and 

Sheet Glass; by Henry Chance, M. A. And Plate Glass, by H. 

G. Harris, Asso. M. Inst. C. E. Illustrated i8mo. . $1.50 

PROCTOR.— A Pocket-Book of Useful Tables and Formulae 
for Marine Engineers : 
By Frank Proctor. Second Edition, Revised and Enlarged. 
Full -bound pocket-book form ...... #1.50 

REGNAULT.— Elements of Chemistry: 
By M. V. Regnault. Translated from the French by T. Forrest 
Betton, M. D., a<nd edited, with Notes, by James C. Booth, Melter 
and Refiner U. S. Mint, and William L. Faber, Metallurgist and 
Mining Engineer. Illustrated by nearly 700 wood-engravings. Com- 
prising nearly 1,500 pages. In two volumes, 8vo., cloth . #7.50 

RICHARDS. — Aluminium : 

Its History, Occurrence, Properties, Metallurgy and Applications, 
including its Alloys. By Joseph W. Richards, A. C, Chemist and 
Practical Metallurgist, Member of the Deutsche Chemische Gesell- 
schaft. Must. Third edition, enlarged and revised (1895) • $6.00 

RIFFAULT, VERGNAUD, and TOUSSAIMT.— A Practical 
Treatise on the Manufacture of Colors for Painting : 
Comprising the Origin, Definition, and Classification of Colors; the 
Treatment of the Raw Materials ; the best Formulae and the Newest 
Processes for the Preparation of every description of Pigment, and 
the Necessary Apparatus and Directions for its Use; Dryers; tha 
Testing. Application, and Qualities of Paints, etc., etc. By MM. 
Riffault, Vergnaud, and Toussaint. Revised and Edited by M. 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 23 

F. Malepeyre. Translated from the French, by A. A. Fesqtjst, 
Chemist and Engineer. Illustrated by Eighty engravings. In one 
vol., 8vo., 659 pages $5.00 

ROPER. — A Catechism of High-Pressure, or Non-Condensing 
Steam -Engines : 

Including the Modelling, Constructing, and Management of Steam- 
Engines and Steam Boilers. With valuable illustrations. By Ste- 
phen Roper, Engineer. Sixteenth edition, revised and enlarged. 
l8mo., tucks, gilt edge ....... $2.00 

ROPER. — Engineer's Handy-Book: 

Containing a full Explanation of the Steam-Engine Indicator, and its 
Use and Advantages to Engineers and Steam Users. With Formulae 
for Estimating the Power of all Classes of Steam-Engines ; also, 
Facts, Figures, Questions, and Tables for Engineers who wish to 
qualify themselves for the United States Navy, the Revenue Service, 
the Mercantile Marine, or to take charge of the Better Class of Sta- 
tionary Steam-Engines. Sixth edition. i6mo.. 690 pages, tucks, 
gih edge #3.50 

ROPER. — Hand-Book of Land and Marine Engines : 
Including the Modelling, Construction, Running, and Management 
of Lane 1 and Marine Engines and Boilers. With illustrations. By 
Stephen Roper, Engineer. Sixth edition. i2mo.,t\ , cks, gilt edge. 

#3-50 
ROPER.— Hand-Book of the Locomotive : 

Including the Construction of Engines and Boilers, and the Construc- 
tion, Management, and Running of Locomotives. By Stephen 
Roper. Eleventh edition. l8mo., tucks, gilt edge . $2.50 

ROPER. — Hand-Book of Modern Steam Fire-Engines. 
With illustrations. By Stephen Roper, Engineer. Fourth edition, 
i2mo., tucks, gilt edge $3-50 

ROPER. — Questions and Answers for Engineers. 

This little book contains all the Questions that Engineers will be 
asked when undergoing an Examination for the purpose of procuring 
Licenses, and they are so plain that any Engineer or Fireman of or 
dinary intelligence may commit them to memory in a short time. By 
Stephen Roper, Engineer. Third edition . . . $3.00 

ROPER. — Use and Abuse of the Steam Boiler. 
By Stephen Roper, Engineer. Eighth edition, with illustrations. 
l8mo., tucks, gilt edge $2.00 

ROSE. — The Complete Practical Machinist : 

Embracing Lathe Work, Vise Work, Drills and Drilling, Taps and 
Dies, Hardening and Tempering, the Making and Use of Tools, 
Tool Grinding, Marking out Work, etc. By Joshua Rose. Illus- 
trated by 356 engravings. Thirteenth edition, thoroughly revised 
and in great part rewritten. In one vol., i2mo., 439 pages #2.50 

ROSE.— Mechanical Drawing Self-Taught: 
Comprising Instructions in the Selection and Preparation of Drawing 
Instruments. Elementary Instruction in Practical Mechanical Draw 



24 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

ln g> together with Examples in Simple Geometry and Elementary 
Mechanism, including Screw Threads, Gear Wheels, Mechanical 
Motions, Engines and Boilers. By Joshua Rose, M. E. Illustrated 
by 330 engravings. 8vo., 313 pages .... $4.00 

ROSE.— The Slide- Valve Practically Explained: 

Embracing simple and complete Practical Demonstrations of tlu 
operation of each element in a Slide-valve Movement, and illustrat- 
ing the effects of Variations in their Proportions by examples care- 
fully selected from the most recent and successful practice. By 
Joshua Rose, M. E. Illustrated by 35 engravings . $1.00 

ROSS. — The Blowpipe in Chemistry, Mineralogy and Geology: 
Containing all Known Methods of Anhydrous Analysis, many Work- 
ing Examples, and Instructions for Making Apparatus. By Lieut.- 
Colonel W. A. Ross, R. A., F. G. S. With 120 Illustrations, 
i2mo #2.00 

SHAW. — Civil Architecture : 

Being a Complete Theoretical and Practical System of Building, con. 
taining the Fundamental Principles of the Art. By Edward Shaw, 
Architect. To which is added a Treatise on Gothic Architecture, etc. 
By Thomas W. Silloway and George M. Harding, Architects. 
The whole illustrated by 102 quarto plates finely engraved on copper. 
Eleventh edition. 4to. ....... $7*50 

SHUNK. — A Practical Treatise on Railway Curves and Loca- 
tion, for Young Engineers. 

By W. F. Shunk, C. E. l2mo. Full ^ound pocket-book form $2.00 

SLATER.— The Manual of Colors and Dye Wares. 
By J. W. Slater. i2mo $3-oo 

SLOAN. — American Houses: 

A variety of Original Designs for Rural Buildings. Illustrated by 
26 colored engravings, with descriptive references. By Samuel 
Sloan, Architect. 8vo. $i-$o 

SLOAN. — Homestead Architecture: 

Containing Forty Designs for Villas, Cottages, and Farm-houses, with 
Eusays on Style, Construction, Landscape Gardening, Furniture, etc., 
etc. Illustrated by upwards of 200 engravings. By Samuel Sloan, 
Architect. 8vo. ..-,.... #3.50 

SLOANE. — Ho,r>e Experiments m Science. 

By T. O'Conor Slcane, E. M., A.M., Ph.D. Illustrated by 91 
engravings. i2mo. ....... $1.50 

SMEATON.— Builder's Pocktt-Companion : 

Containing the Elements of Building, Surveying, and Architecture; 
with Practical Rules and Instructions connected with the subject. 
By A. C. Smeaton, Civil Engineer, etc. i2mo. . . $1.50 

SMITH.— A Manual of Political Economy. 
By E. Peshine Smith. A New Edition, to which is added a full 
Index. i2mo. $E 25 



HENRY CAREY EAIRD & CO.'S CATALOGUE. 25 



SMITH.— Parks and Pleasure - Grounds : 

Or Practical Notes on Country Residences, Villas, Public Parks, and 
Gardens. By Charles H. J. Smith, Landscape Gardener and 
Garden Architect, etc., etc. i2mo. .... $2.00. 

SMITH.— The Dyer's Instructor: 

Comprising Practical Instructions in the Art of Dyeing Silk, Cotton, 
Wool, and Worsted, and Woolen Goods; containing nearly 800 
Receipts. To which is added a Treatise on the Art of Padding; ancij 
the Printing of Silk Warps, Skeins, and Handkerchiefs, and the 
various Mordants and Colors for the different styles of such work. 
By David Smith, Pattern Dyer. i2mo. ... $2.00 

SMYTH. A Rudimentary Treatise on Coal and Coal-Mining. 

By Warrington W. Smyth, M. A., F. R. G., President R. G. S. 
of Cornwall. Fifth edition, revised and corrected. With numer- 
ous illustrations. l2mo. $ l -7$ 

SN IV ELY.— Tables for Systematic Qualitative Chemical AnaL 
ysis. 
By John H. Snively, Phr. D. 8vo #i-°o 

SNIVELY.— The Elements of Systematic Qualitative chemical 
Analysis : 
A Hand-book for Beginners. By John H. Snively, Phr. D. ibmo. 

$2.00 

STOKES. — The Cabinet-Maker and Upholsterer's Companion : 

Comprising the Art of Drawing, as applicable to Cabinet Work; 
Veneering, Inlaying, and Buhl-Work ; the Art of Dyeing and Stain- 
ing Wood, Ivory, Bone, Tortoise-Shell, etc. Directions for Lacker- 
ing, Japanning, and Varnishing; to make French Polish, Glues, 
Cements, and Compos:."- ns; with numerous Receipts, useful to work 
men generally. Bv Stokes. Illustrated. A New Edition, with 
an Appendix upor .ench Polishing, Staining, Imitating, Varnishing, 
etc., etc. i2mo # x - 2 5 

STRENGTH AND OTHER PROPERTIES OF METALS; 
Reports of Experiments on the Strength and other Properties of 
Metals for Cannon. With a Description of the Machines for Testing 
Metals, and of the Classification of Cannon in service. By Officers 
of the Ordnance Department, U. S. Army. By authority of the Secre. 
taryofWar. Illustrated by 25 large steel plates. Quarto. #10.00 

BULLIVAN. — Protection to Native Industry. 

By Sir Edward Sullivan, Baronet, author of " Ten Chapters on 
Social Reforms." 8vo #i-oo 

SULZ.— A Treatise on Beverages : 

Or the Complete Practical Bottler. Full instructions for Laboratory 
Work, with Original Practical Recipes for all kinds of Carbonated 
Drink's, Mineral Waters, Flavorings. Extracts, Syrups, etc. By 
Chas. Herman Sulz, Technical Cherdst ana Practical Bottler 
Illustrated by 428 Engraving. 8it< i>p. ^v*> • - #10.00 



26 HENRY CAREY BAIRt> & CO.'S CATALOGUE. 

SYME. — Outlines of an Industrial Science. 
By David Syme. i2mo. . . ... $2.00 

TABLES SHOWING THE WEIGHT OF ROUND, 
SQUARE, AND FLAT BAR IRON, STEEL, ETC., 

By Measurement. Cloth • 63 

TAYLOR.— Statistics of Coal : 

Including Mineral Bituminous Substances employed in Arts and 
Manufactures ; with their Geographical, Geological, and Commercial 
Distribution and Amount of Production and Consumption on the 
American Continent. With Incidental Statistics of the Iron Manu- 
facture. By R. C. Taylor. Second edition, revised by S. S. Halde« 
MAN. Illustrated by five Maps and many wood engravings. 8vo., 
cloth #6.00 

TEMPLETON. — The Practical Examinator on Steam and the 
Steam -Engine: 
With Instructive References relative thereto, arranged for the Use of 
Engineers, Students, and others. By William Templeton, En- 
gineer. l2mo. ....•••• #1.00 

THAUSING.— The Theory and Practice of the Preparation of 
Malt and the Fabrication of Beer : 
With especial reference to the Vienna Process of Brewing. Elab- 
orated from personal experience by Julius E. Thausing, Professor 
at the School for Brewers, and at the Agricultural Institute, Modling, 
near Vienna. Translated from the German by William T. Brannt, 
Thoroughly and elaborately edited, with much American matter, and 
according to the latest and most Scientific Practice, by A. Schwarz 
and Dr. A. H. Bauer. Illustrated by 140 Engravings. 8vo., 815 
pages $10.00 

THOMAS. — The Modern Practice of Photography: 

By R. W. Thomas, F. C. S. 8vo. . . 25 

THOMPSON. — Political Economy. With Especial Reference 
to the Industrial History of Nations : 
By Robert E. Thompson, M. A., Professor of Social Science in the 
University of Pennsylvania. l2mo. .... $1.5° 

THOMSON.— Freight Charges Calculator: 
By Andrew Thomson, Freight Agent. 241110. . . $1.25 

TURNER'S (THE) COMPANION: 

Containing Instructions in Concentric, Elliptic, and Eccentric Turn, 
hig; also various Plates of Chucks, Tools, and Instruments; and 
Directions for using the Eccentric Cutter, Drill, Vertical Cutter, and 
Circular Rest; with Patterns and Instructions for working them- 
l2mo $1.25 

TURNING : Specimens of Fancy Turning Executed on the 

Hand or Foot-Lathe : ' 

With Geometric, Oval, and Eccentric Chucks, and Elliptical Cutting 

Frame. By an Amateur. Illustrated by 30 exquisite Photographs. 

4to $3-°° 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 



VAILE.— Galvanized-Iron Cornice- Worker's Manual : 

Containing Instructions in Laying out the Different Mitres and 
Making Patterns for all kinds of Plain and Circular Work Also 
Tables of Weights, Areas and Circumferences of Circles, and o her 
Matter calculated to Benefit the Trade. By Charles A. Vaile. 
Illustrated by twenty-one plates. 4to P5- 

VTT T E On Artificial Manures : 

ThelrChemkal Selection and Scientific Application to Agriculture. 
Is^riesof Sufres given at the Experimental Farm at Vincennes 
A series oi i^eciu g Georges Ville. Translated and 
ESby^L^CKOOKi, F. R. S. Illustrated by thirty^ 
engravings. 8vo., 450 pages 

VILLE —The School of Chemical Manures : 

Or KemenTary Principles in the Use of Fertilizing Agents. From 

the S "of M. Geo! Ville, by A. A. Fesquet, Chemist and En- 

gineer. With Illustrations. l2mo. • ■ • • *>*• S 

VOGDES.-The Architect's and Builder's Pocket- Companion 

oSStSfrf-^tbat Comprehensive S^^SS^ 
decimals Geometry and Mensuration; with Tables of United States 
MeasmS Sizes, Weights, Strengths, etc., of Iron Wood, Stone 
S Cement and Concretes, Quantities of Materials in given Sizes 
Sd Dimensions of Wood, Brick and Stone; and full and complete 
Klls of Prices for Carpenter's Work and Painting; also Rules for 
Computing Valuing Brick and Brick Work, Stone Work Paint- 
ino PlaTterincr, with 1 Vocabulary of Technical Terms etc. By 
f!1nk W Vo & gdes, Architect, Indianapolis, Ind [Enlarged revised, 
and corrected. In' one volume, 368 pages, full-bound, pocket-book 
form, gilt edges • * | * ^ 

VAN h CLEVE.'— The English and American Mechanic : 

Comprising a Collection of Over Three Thousand Receipts Rules, 

an?Tabte, designed for the Use of every Mechanic and Manufac, 

turer. By B. Frank Van Cleve. Illustrated. 500 pp. i?mo. $2.00 

WAHNSCHAFFE.— A Guide to the Scientific Examination 

Comprising' Select Methods of Mechanical and Chemical Analysis 
and Physical Investigation. Translated from the German of Dr. F. 
WahnJchaffe. With additions by William T. Brannt. Illus- 
trated by 25 engravings. l2mo. 177 pages . . . *i-5° 

WALL.— Practical Graining : • , • • , 

WiTh Descriptions of Colors Employed and Tools Used. Illustrated 
bv 47 Colored Plates, Representing the Various Woods Used * 
Interior Finishing. By William E. Wall. 8vo. . #2.50 

WALTON.— Coal-Mining Described and Illustrated: 

Bv Thomas H. Walton, Mining Engineer. Illustrated by 24 Jarge 
and elaborate Plates, after Actual Workings ana Apparatus. #5.00 



28 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

WARE.— The Sugar Beet. 

Including a History of the Beet Sugar Industry in Europe, Varieties 
of the Sugar Beet, Examination, Soils, Tillage, Seeds and Sowings 
Yield and Cost of Cultivation, Harvesting, Transportation, Conserva 
tion, Feeding Qualities of the Beet and of the Pulp, etc. By Lewis 
S. Ware, C. E., M. E. Illustrated by ninety engravings. 8vo. 

$4.QQ 

WARN. — The Sheet-Metal Worker's Instructor: 

For Zinc, Sheet-Iron, Copper, and Tin-Plate Workers, etc. Contain- 
ing a selection of Geometrical Problems ; also, Practical and Simple 
Rules for Describing the various Patterns required in the different 
branches of the above Trades. By Reuben H. Warn, Practical 
Tin-Plate Worker. To which is added an Appendix, containing 
Instructions for Boiler-Making, Mensuration of Surfaces and Solids, 
Rules for Calculating the Weights of different Figures of Iron and 
Steel, Tables of the Weights of Iron, Steel, etc. Illustrated by thirty- 
two Plates and thirty-seven Wood Engravings. 8vo. . $3-O0 

WARNER. — New Theorems, Tables, and Diagrams, for the 
Computation of Earth-work : 
Designed for the use of Engineers in Preliminary and Final Estimates 
of Students in Engineering, and of Contractors and other non-profes. 
sional Computers. In two parts, with an Appendix. Part I. A Prac- 
tical Treatise; Part II. A Theoretical Treatise, and the Appendix. 
Containing Notes to the Rules and Examples of Part L; Explana- 
tions of the Construction of Scales, Tables, and Diagrams, and a 
Treatise upon Equivalent Square Bases and Equivalent Level Heights. 
The whole illustrated by numerous original engravings, comprising 
explanatory cuts for Definitions and Problems, Stereometric Scales 
and Diagrams, and a series of Lithographic Drawings from Models ; 
Showing all the Combinations of Solid Forms which occur in Railroad 
Excavations and Embankments. By John Warner, A. M., Mining 
and Mechanical Engineer. Illustrated by 14 Plates. A new, revised 
and improved edition. 8vo. ...... $4.00 

WATSON.— A Manual of the Hand-Lathe : 

Comprising Concise Directions for Working Metals of all kinds, 
Ivory, Bone and Precious Woods; Dyeing, Coloring, and French 
Polishing; Inlaying by Veneers, and various methods practised to 
produce Elaborate work with Dispatch, and at Small Expense. By 
Egbert P. Watson, Author of " The Modern Practice of American 
Machinists and Engineers." Illustrated by 78 engravings. $l.SO 

WATSON. — The Modern Practice of American Machinists and 
Engineers 

Including the Construction, Application, and Use of Drills, Lathe 
Tools, Cutters for Boring Cylinders, and Hollow-work generally, with 
the most Economical Speed for the same ; the Results verified by 
Actual Practice at the Lathe, the Vise, and on the Floor. Togethe* 



HENRY CAREY BA1RD & CO.'S CATALOGUE. 2q 

with Workshop Management, Economy of Manufacture, the Steam 
Engine, Boilers, Gears, Belting, etc., etc. By Egbert P. Watson. 
Illustrated by eighty-six engravings. l2mo. . . . #2.50 

WATSON.— The Theory and Practice of the Art of Weaving 
by Hand and Power • 
With Calculations and Tables for the Use of those connected with the 
Trade. By John Watson, Manufacturer and Practical Machine- 
Maker. Illustrated by large Drawings of the best Power Looms. 
8vo. . $6.oo' 

WATT.— The Art of Soap Making: 

A Practical Hand-book of the Manufacture of Hard and Soft Soaps, 
Toilet Soaps, etc., including many New Processes, and a Chapter on 
the Recovery of Glycerine from Waste Leys. By ALEXANDER 
Watt. 111. i2mo. $3.00 

WEATKERLY.- Treatise on the Art of Boiling Sugar, Crys- 
tallizing, Lozenge-making, Comfits, Gum Goods, 

And other processes for Confectionery, etc., in which are explained, 
in an easy and familiar manner, the various Methods of Manufactur- 
ing every Description of Raw and Refined Sugar Goods, as sold by 
Confectioners and others. i2mo. . . . . . $l-5<s 

WIGHT WICK. —Hints to Young Architects: 
Comprising Advice to those who, while yet at school, are destined 
to the Proiession; to such as, having passed their pupilage, are about 
to travel ; and to those who, having completed their education, are 
about to practise. Together with a Model Specification involving a 
great variety of instructive and suggestive matter. By George 
Wjghtwick, Architect. A new edition, revised and considerably 
enlarged ; comprising Treatises on the Principles of Construction 
and Design. By G. Huskisson Guillaume, Architect. Numerous 
^lustrations. One vol. i2mo. ...... $2.O0 

W ILL. — Tables of Qualitative Chemical Analysis. 

With an Introductory Chapter on the Course of Analysis. By Pro- 
fessor Heinrich Will, of Giessen, Germany. Third American, 
from the eleventh German edition. Edited by Charles F. Himes, 
Ph. D., Professor of Natural Science, Dickinson College, Carlisle, Pa 
8vo. . I1.50 

WILLIAMS.— On Heat and Steam : 

Embracing New Views of Vaporization, Condensation, and Explo- 
sion. By Charles Wye Williams, A. I. C. E. Illustrated Svo. 

WILSON.— A Treatise on Steam Boilers : 

Their Strength, Construction, and Economical Working. By Robert 
Wilson. Illustrated i2mo $2.50 

V\ILSON. — First Principles of Political Economy: 
With Reference to Statesmanship and the Progress of Civilization. 
By Professor W. D. Wilson, of the Cornell University. A new and 
revised edition. i2mo. $1.50 



30 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

WOHLER. — A Hand-Bookof Mineral Analysis : 

By F. Wohler, Professor of Chemistry in the University of Gottin- 
gen. Edited by Henry B. Nason, Professor of Chemistry in the 
Renssalaer Polytechnic Institute, Troy, New York. Illustrated. 
i2mo $2.50 

WORSSAM. — On Mechanical Saws: 

From the Transactions of the Society of Engineers, 1869. By S. W. 
Worssam, Jr. Illustrated by eighteen large plates. 8vo. 32.50 



RECENT ADDITIONS. 

BRANNT. — Varnishes, Lacquers, Printing Inks and Sealing - 
Waxes : 

Their Raw Materials and their Manufacture, to which is added the 
Art of Varnishing and Lacquering, including the Preparation of Put- 
ties and of Stains for Wood, Ivory, Bone, Horn, and Leather. By 
William T. Brannt. Illustrated by 39 Engravings, 338 pages. 

iamo I3. 00 

BRANNT — The Practical Scourer and Garment Dyer: 

Comprising Dry or Chemical Cleaning ; the Art of Removing Stains ; 
Fine Washing ; Bleaching and Dyeing of Straw Hats, Gloves, and 
Feathers of all kinds; Dyeing of Worn Clothes of all fabrics, in- 
cluding Mixed Goods, by One Dip; and the Manufacture of Soaps 
and Fluids for Cleansing Purposes. Edited by William T. Brannt, 
Editor of " The Techno-Chemical Receipt Book." Illustrated. 
203 pages. i2mo. ....... $2.00 

BRANNT.— Petroleum . 

Its History, Origin, Occurrence, Production, Physical and Chemical 
Constitution, Technology, Examination and Uses; Together with 
the Occurrenee and Uses of Natural Gas. Edited chiefly from the 
German of Prof. Hans Hoefer and Dr. Alexander Veith, by Wm. 
T. Brannt. Illustrated by 3 Plates and 284 Engravings. 743 pp. 
8vo. $7.50 

BRANNT. — A Practical Treatise on the Manufacture of Vine- 
gar and Acetates, Cider, and Fruit- Wines ; 
Preservation of Fruits and Vegetables by Canning and Evaporation; 
Preparation of Fruit-Butters, Jellies, Marmalades, Catchups, Pickles, 
Mustards, etc. Edited from various sources. By William T. 
Brannt. Illustrated by 79 Engravings. 479 pp. 8vo. $5.00 

BRANNT.— The Metal Worker's Handy-Book of Receipts 
and Processes : 

Being a Collection of Chemical Formulas and Practical Manipula- 
tions for the working of all Metals ; including the Decoration and 
Beautifying of Articles Manufactured therefrom, as well as their 
Preservation. Edited from various sources. By William T. 
Brannt. Illustrated. i2mo. £2.50 



HENRY CAREY BAIRD & CO.'S CATALOGUE. 3r 

DEITE. — A Practical Treatise on the Manufacture cf Per* 
furriery : 
Comprising directions for making all kinds of Perfumes, Sachet 
Powders, Fumigating Materials, Dentifrices, Cosmetics, etc., with a 
full account of the Volatile Oils, Balsams, Resins, and other Natural 
and Artificial Perfume-substances, including the Manufacture of 
Fruit Ethers, and tests of their purity. By Dr. C. Deite, assisted 
by L. Borchert, F. Eichbaum, E. Kugler, H. Toeffner, and 
other experts. From the German, by Wm. T. Brannt. 28 Engrav- 
ings. 358 pages. 8vo. . . ... . . $3-QO 

EDWARDS. — American Marine Engineer, Theoretical and 
Practical : 
With Examples of the latest and most approved American Practice. 
By Emory Edwards. 85 illustrations. i2mo. . . $2.50 

EDWARDS. — 900 Examination Questions and Answers: 

For Engineers and Firemen (Land and Marine) who desire to ob- 
tain a United States Government or State License. Pocket-book 

form, gilt edge . $1.50 

POSSELT. — Technology of Textile Design : 
Being a Practical Treatise on the Construction and Application of 
Weaves for all Textile Fabrics, with minute reference to the latest 
Inventions for Weaving. Containing also an Appendix, showing 
the Analysis and giving the Calculations necessary for the Manufac* 
ture of the various Textile Fabrics. By E. A. Posselt, Head 
Master Textile Department, Pennsylvania Museum and School of 
Industrial Art, Philadelphia, with over 1000 illustrations. 29a 
pages. 4to $5-og 

POSSELT. — The Jacquard Machine Analysed and Explained: 
With an Appendix on the Preparation of Jacquard Cards, and 
Practical Hints to Learners of Jacquard Designing. By E. A. 
Posselt. With 230 illustrations and numerous diagrams. 127 pp. 
4to #3.00 

POSSELT.— The Structure of Fibres, Yarns and Fabrics: 
Being a Practical Treatise for the Use of all Persons Employed in 
the Manufacture of Textile Fabrics, containing a Description of the 
Growth and Manipulation of Cotton, Wool, Worsted, Silk Flax, 
Jute, Ramie, China Grass and Hemp, and Dealing with all Manu- 
facturers' Calculations for Every Class of Material, also Giving 
Minute Details for the Structure of all kinds of Textile Fabrics, and 
an Appendix of Arithmetic, specially adapted for Textile Purposes. 
By E. A. Posselt. Over 400 Illustrations, quarto. . #10.00 

RICH. — Artistic Horse-Shoeing: 

A Practical and Scientific Treatise, giving Improved Methods of 
Shoeing, with Special Directions for Shaping Shoes to Cure Different 
Diseases of the Foot, and for the Correction of Faulty Action in 
Trotters. By George E. Rich. 62 Illustrations. 153 pages. 
izmo gf.oo 



32 HENRY CAREY BAIRD & CO.'S CATALOGUE. 

RICHARDSON.— Practical Blacksmithing : 

A Collection of Articles Contributed at Different Times by Skilled 
Workmen to the columns of " The Blacksmith and Wheelwright," 
and Covering nearly the Whole Range of Blacksmithing, from the 
Simplest Job of Work to some of the Most Complex Forgings, 
Compiled and Edited by M. T. Richardson. 

Vol. I. 210 Illustrations. 224 pages. i2mo. . . $1.00 

Vol. II. 230 Illustrations. 262 pages. i2mo. . , $1.00 
Vol. III. 390 Illustrations. 307 pages. i2mo. . . $1.00 
Vol. IV. 226 Illustrations. 276 pages. l2mo. , . $1.00 

RICHARDSON. — The Practical Horseshoer: 
Being a Collection of Articles on Horseshoeing in all its Branches 
which have appeared from time to time in the columns of "The 
Blacksmith and Wheelwright," etc. Compiled and edited by M. T. 
Richardson. 174 illustrations $1.00 

ROPER. — Instructions and Suggestions for Engineers and 
Firemen : 
By Stephen Roper, Engineer. i8mo. Morocco . $2.00 

ROPER. — The Steam Boiler: Its Care and Management: 
By Stephen Roper, Engineer. 12010., tuck, gilt edges. $2.00 

ROPER. — The Young Engineer's Own Book: 

Containing an Explanation of the Principle and Theories on which 
the Steam Engine as a Prime Mover is Based. By Stephen Roper, 
Engineer. 160 illustrations, 363 pages. i8mo., tuck . $3-00 

ROSE. — Modern Steam-Engines : 

An Elementary Treatise upon the Steam-Engine, written in Plain 
language ; for Use in the Workshop as well as in the Drawing Office. 
Giving Full Explanations of the Construction of Modern Steanv 
Engines : Including Diagrams showing their Actual operation. To- 
gether with Complete but Simple Explanations of the operations of 
Various Kinds of Valves, Valve Motions, and Link Motions, etc., 
thereby Enabling the Ordinary Engineer to clearly Understand the 
Principles Involved in their Construction and Use, and to Plot out 
their Movements upon the Drawing Board. By Joshua Rose. M. E. 
Illustrated by 422 engravings. Revised. 358 pp. . . #6.00 

ROSE. — Steam Boilers: 

A Practical Treatise on Boiler Construction and Examination, for the 
Use of Practical Boiler Makers, Boiler Users, and Inspectors; and 
embracing in plain figures all the calculations necessary in Designing 
or Classifying Steam Boilers. By Joshua Rose, M. E. Illustrated 

by 73 engravings. 250 pages. 8vo $2,150 

SCHRIBER.— The Complete Carriage and Wagon Painter: 
A Concise Compendium of the Art of Painting Carriages, Wagons, 
and Sleighs, embracing Full Directions in all the Various Branches, 
including Lettering, Scrolling, Ornamenting, Striping, Varnishing, 
and Coloring, with numerous Recipes for Mixing Colors. 73 Illus- 
trations. 177 pp. i2mo. c $1.00 



L&JLM7 



■I fj 






iOo. 









,-\ 



0?. 









V** 






^ 




V 

•V s - 'tt - 









' 



*** > O 



.& 



x 0o 



^ x 










',*«?, 



o* _\ 



^ s? 









V ^ 






V> *%, 






*$ % 









■/■ 



^. v* 



: ^ 



A 






- 



\0 o 



o5 ^ 









./• v 






V 



.\* 



<f <j\ 






'>,. 



*v o 



*N 









^ ■** 



sV ■ 






V- \v 






-C- A N 



0^' ' r V 









*, 



tt. ' 



, *V> 



^ ^ 






.A^ .*' 




















■<r r .v\ x 



. 









& ' . \- 



,\ 



^ N -" 



A' 



^ rA 




t/- c x 






y. V- 



<•> • OA 

% ->. 

-P \ 

•• / --O A^ 









O.N 



^ ^ 



W 



. 



,^ 



^ 



0^ 



A " ^3 



''% 



A 















LIBRARY OF CONGRESS 

liiiiiiiiiiiiiiiL 

018 449 046 8 % 



